discussion on research paper example

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How to Write Discussions and Conclusions

How to Write Discussions and Conclusions

The discussion section contains the results and outcomes of a study. An effective discussion informs readers what can be learned from your experiment and provides context for the results.

What makes an effective discussion?

When you’re ready to write your discussion, you’ve already introduced the purpose of your study and provided an in-depth description of the methodology. The discussion informs readers about the larger implications of your study based on the results. Highlighting these implications while not overstating the findings can be challenging, especially when you’re submitting to a journal that selects articles based on novelty or potential impact. Regardless of what journal you are submitting to, the discussion section always serves the same purpose: concluding what your study results actually mean.

A successful discussion section puts your findings in context. It should include:

the results of your research,
a discussion of related research, and
a comparison between your results and initial hypothesis.

Tip: Not all journals share the same naming conventions.

You can apply the advice in this article to the conclusion, results or discussion sections of your manuscript.

Our Early Career Researcher community tells us that the conclusion is often considered the most difficult aspect of a manuscript to write. To help, this guide provides questions to ask yourself, a basic structure to model your discussion off of and examples from published manuscripts.

Questions to ask yourself:

Was my hypothesis correct?
If my hypothesis is partially correct or entirely different, what can be learned from the results?
How do the conclusions reshape or add onto the existing knowledge in the field? What does previous research say about the topic?
Why are the results important or relevant to your audience? Do they add further evidence to a scientific consensus or disprove prior studies?
How can future research build on these observations? What are the key experiments that must be done?
What is the “take-home” message you want your reader to leave with?

How to structure a discussion

Trying to fit a complete discussion into a single paragraph can add unnecessary stress to the writing process. If possible, you’ll want to give yourself two or three paragraphs to give the reader a comprehensive understanding of your study as a whole. Here’s one way to structure an effective discussion:

Writing Tips

While the above sections can help you brainstorm and structure your discussion, there are many common mistakes that writers revert to when having difficulties with their paper. Writing a discussion can be a delicate balance between summarizing your results, providing proper context for your research and avoiding introducing new information. Remember that your paper should be both confident and honest about the results!

Read the journal’s guidelines on the discussion and conclusion sections. If possible, learn about the guidelines before writing the discussion to ensure you’re writing to meet their expectations.
Begin with a clear statement of the principal findings. This will reinforce the main take-away for the reader and set up the rest of the discussion.
Explain why the outcomes of your study are important to the reader. Discuss the implications of your findings realistically based on previous literature, highlighting both the strengths and limitations of the research.
State whether the results prove or disprove your hypothesis. If your hypothesis was disproved, what might be the reasons?
Introduce new or expanded ways to think about the research question. Indicate what next steps can be taken to further pursue any unresolved questions.
If dealing with a contemporary or ongoing problem, such as climate change, discuss possible consequences if the problem is avoided.
Be concise. Adding unnecessary detail can distract from the main findings.

Don’t

Rewrite your abstract. Statements with “we investigated” or “we studied” generally do not belong in the discussion.
Include new arguments or evidence not previously discussed. Necessary information and evidence should be introduced in the main body of the paper.
Apologize. Even if your research contains significant limitations, don’t undermine your authority by including statements that doubt your methodology or execution.
Shy away from speaking on limitations or negative results. Including limitations and negative results will give readers a complete understanding of the presented research. Potential limitations include sources of potential bias, threats to internal or external validity, barriers to implementing an intervention and other issues inherent to the study design.
Overstate the importance of your findings. Making grand statements about how a study will fully resolve large questions can lead readers to doubt the success of the research.

Snippets of Effective Discussions:

Consumer-based actions to reduce plastic pollution in rivers: A multi-criteria decision analysis approach

Identifying reliable indicators of fitness in polar bears

How to Write a Great Title
How to Write an Abstract
How to Write Your Methods
How to Report Statistics
How to Edit Your Work

The contents of the Peer Review Center are also available as a live, interactive training session, complete with slides, talking points, and activities. …

The contents of the Writing Center are also available as a live, interactive training session, complete with slides, talking points, and activities. …

There’s a lot to consider when deciding where to submit your work. Learn how to choose a journal that will help your study reach its audience, while reflecting your values as a researcher…

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Research Guides

Organizing Your Social Sciences Research Paper

8. The Discussion
Purpose of Guide
Design Flaws to Avoid
Independent and Dependent Variables
Glossary of Research Terms
Reading Research Effectively
Narrowing a Topic Idea
Broadening a Topic Idea
Extending the Timeliness of a Topic Idea
Academic Writing Style
Applying Critical Thinking
Choosing a Title
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Paragraph Development
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Using Non-Textual Elements
Limitations of the Study
Common Grammar Mistakes
Writing Concisely
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Footnotes or Endnotes?
Further Readings
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USC Libraries Tutorials and Other Guides
Bibliography

The purpose of the discussion section is to interpret and describe the significance of your findings in relation to what was already known about the research problem being investigated and to explain any new understanding or insights that emerged as a result of your research. The discussion will always connect to the introduction by way of the research questions or hypotheses you posed and the literature you reviewed, but the discussion does not simply repeat or rearrange the first parts of your paper; the discussion clearly explains how your study advanced the reader's understanding of the research problem from where you left them at the end of your review of prior research.

Annesley, Thomas M. “The Discussion Section: Your Closing Argument.” Clinical Chemistry 56 (November 2010): 1671-1674; Peacock, Matthew. “Communicative Moves in the Discussion Section of Research Articles.” System 30 (December 2002): 479-497.

Importance of a Good Discussion

The discussion section is often considered the most important part of your research paper because it:

Most effectively demonstrates your ability as a researcher to think critically about an issue, to develop creative solutions to problems based upon a logical synthesis of the findings, and to formulate a deeper, more profound understanding of the research problem under investigation;
Presents the underlying meaning of your research, notes possible implications in other areas of study, and explores possible improvements that can be made in order to further develop the concerns of your research;
Highlights the importance of your study and how it can contribute to understanding the research problem within the field of study;
Presents how the findings from your study revealed and helped fill gaps in the literature that had not been previously exposed or adequately described; and,
Engages the reader in thinking critically about issues based on an evidence-based interpretation of findings; it is not governed strictly by objective reporting of information.

Annesley Thomas M. “The Discussion Section: Your Closing Argument.” Clinical Chemistry 56 (November 2010): 1671-1674; Bitchener, John and Helen Basturkmen. “Perceptions of the Difficulties of Postgraduate L2 Thesis Students Writing the Discussion Section.” Journal of English for Academic Purposes 5 (January 2006): 4-18; Kretchmer, Paul. Fourteen Steps to Writing an Effective Discussion Section. San Francisco Edit, 2003-2008.

Structure and Writing Style

I. General Rules

These are the general rules you should adopt when composing your discussion of the results :

Do not be verbose or repetitive; be concise and make your points clearly
Avoid the use of jargon or undefined technical language
Follow a logical stream of thought; in general, interpret and discuss the significance of your findings in the same sequence you described them in your results section [a notable exception is to begin by highlighting an unexpected result or a finding that can grab the reader's attention]
Use the present verb tense, especially for established facts; however, refer to specific works or prior studies in the past tense
If needed, use subheadings to help organize your discussion or to categorize your interpretations into themes

II. The Content

The content of the discussion section of your paper most often includes :

Explanation of results : Comment on whether or not the results were expected for each set of findings; go into greater depth to explain findings that were unexpected or especially profound. If appropriate, note any unusual or unanticipated patterns or trends that emerged from your results and explain their meaning in relation to the research problem.
References to previous research : Either compare your results with the findings from other studies or use the studies to support a claim. This can include re-visiting key sources already cited in your literature review section, or, save them to cite later in the discussion section if they are more important to compare with your results instead of being a part of the general literature review of prior research used to provide context and background information. Note that you can make this decision to highlight specific studies after you have begun writing the discussion section.
Deduction : A claim for how the results can be applied more generally. For example, describing lessons learned, proposing recommendations that can help improve a situation, or highlighting best practices.
Hypothesis : A more general claim or possible conclusion arising from the results [which may be proved or disproved in subsequent research]. This can be framed as new research questions that emerged as a consequence of your analysis.

III. Organization and Structure

Keep the following sequential points in mind as you organize and write the discussion section of your paper:

Think of your discussion as an inverted pyramid. Organize the discussion from the general to the specific, linking your findings to the literature, then to theory, then to practice [if appropriate].
Use the same key terms, narrative style, and verb tense [present] that you used when describing the research problem in your introduction.
Begin by briefly re-stating the research problem you were investigating and answer all of the research questions underpinning the problem that you posed in the introduction.
Describe the patterns, principles, and relationships shown by each major findings and place them in proper perspective. The sequence of this information is important; first state the answer, then the relevant results, then cite the work of others. If appropriate, refer the reader to a figure or table to help enhance the interpretation of the data [either within the text or as an appendix].
Regardless of where it's mentioned, a good discussion section includes analysis of any unexpected findings. This part of the discussion should begin with a description of the unanticipated finding, followed by a brief interpretation as to why you believe it appeared and, if necessary, its possible significance in relation to the overall study. If more than one unexpected finding emerged during the study, describe each of them in the order they appeared as you gathered or analyzed the data. As noted, the exception to discussing findings in the same order you described them in the results section would be to begin by highlighting the implications of a particularly unexpected or significant finding that emerged from the study, followed by a discussion of the remaining findings.
Before concluding the discussion, identify potential limitations and weaknesses if you do not plan to do so in the conclusion of the paper. Comment on their relative importance in relation to your overall interpretation of the results and, if necessary, note how they may affect the validity of your findings. Avoid using an apologetic tone; however, be honest and self-critical [e.g., in retrospect, had you included a particular question in a survey instrument, additional data could have been revealed].
The discussion section should end with a concise summary of the principal implications of the findings regardless of their significance. Give a brief explanation about why you believe the findings and conclusions of your study are important and how they support broader knowledge or understanding of the research problem. This can be followed by any recommendations for further research. However, do not offer recommendations which could have been easily addressed within the study. This would demonstrate to the reader that you have inadequately examined and interpreted the data.

IV. Overall Objectives

The objectives of your discussion section should include the following: I. Reiterate the Research Problem/State the Major Findings

Briefly reiterate the research problem or problems you are investigating and the methods you used to investigate them, then move quickly to describe the major findings of the study. You should write a direct, declarative, and succinct proclamation of the study results, usually in one paragraph.

II. Explain the Meaning of the Findings and Why They are Important

No one has thought as long and hard about your study as you have. Systematically explain the underlying meaning of your findings and state why you believe they are significant. After reading the discussion section, you want the reader to think critically about the results and why they are important. You don’t want to force the reader to go through the paper multiple times to figure out what it all means. If applicable, begin this part of the section by repeating what you consider to be your most significant or unanticipated finding first, then systematically review each finding. Otherwise, follow the general order you reported the findings presented in the results section.

III. Relate the Findings to Similar Studies

No study in the social sciences is so novel or possesses such a restricted focus that it has absolutely no relation to previously published research. The discussion section should relate your results to those found in other studies, particularly if questions raised from prior studies served as the motivation for your research. This is important because comparing and contrasting the findings of other studies helps to support the overall importance of your results and it highlights how and in what ways your study differs from other research about the topic. Note that any significant or unanticipated finding is often because there was no prior research to indicate the finding could occur. If there is prior research to indicate this, you need to explain why it was significant or unanticipated. IV. Consider Alternative Explanations of the Findings

It is important to remember that the purpose of research in the social sciences is to discover and not to prove . When writing the discussion section, you should carefully consider all possible explanations for the study results, rather than just those that fit your hypothesis or prior assumptions and biases. This is especially important when describing the discovery of significant or unanticipated findings.

V. Acknowledge the Study’s Limitations

It is far better for you to identify and acknowledge your study’s limitations than to have them pointed out by your professor! Note any unanswered questions or issues your study could not address and describe the generalizability of your results to other situations. If a limitation is applicable to the method chosen to gather information, then describe in detail the problems you encountered and why. VI. Make Suggestions for Further Research

You may choose to conclude the discussion section by making suggestions for further research [as opposed to offering suggestions in the conclusion of your paper]. Although your study can offer important insights about the research problem, this is where you can address other questions related to the problem that remain unanswered or highlight hidden issues that were revealed as a result of conducting your research. You should frame your suggestions by linking the need for further research to the limitations of your study [e.g., in future studies, the survey instrument should include more questions that ask..."] or linking to critical issues revealed from the data that were not considered initially in your research.

NOTE: Besides the literature review section, the preponderance of references to sources is usually found in the discussion section . A few historical references may be helpful for perspective, but most of the references should be relatively recent and included to aid in the interpretation of your results, to support the significance of a finding, and/or to place a finding within a particular context. If a study that you cited does not support your findings, don't ignore it--clearly explain why your research findings differ from theirs.

V. Problems to Avoid

Do not waste time restating your results . Should you need to remind the reader of a finding to be discussed, use "bridge sentences" that relate the result to the interpretation. An example would be: “In the case of determining available housing to single women with children in rural areas of Texas, the findings suggest that access to good schools is important...," then move on to further explaining this finding and its implications.
As noted, recommendations for further research can be included in either the discussion or conclusion of your paper, but do not repeat your recommendations in the both sections. Think about the overall narrative flow of your paper to determine where best to locate this information. However, if your findings raise a lot of new questions or issues, consider including suggestions for further research in the discussion section.
Do not introduce new results in the discussion section. Be wary of mistaking the reiteration of a specific finding for an interpretation because it may confuse the reader. The description of findings [results section] and the interpretation of their significance [discussion section] should be distinct parts of your paper. If you choose to combine the results section and the discussion section into a single narrative, you must be clear in how you report the information discovered and your own interpretation of each finding. This approach is not recommended if you lack experience writing college-level research papers.
Use of the first person pronoun is generally acceptable. Using first person singular pronouns can help emphasize a point or illustrate a contrasting finding. However, keep in mind that too much use of the first person can actually distract the reader from the main points [i.e., I know you're telling me this--just tell me!].

Analyzing vs. Summarizing. Department of English Writing Guide. George Mason University; Discussion. The Structure, Format, Content, and Style of a Journal-Style Scientific Paper. Department of Biology. Bates College; Hess, Dean R. "How to Write an Effective Discussion." Respiratory Care 49 (October 2004); Kretchmer, Paul. Fourteen Steps to Writing to Writing an Effective Discussion Section. San Francisco Edit, 2003-2008; The Lab Report. University College Writing Centre. University of Toronto; Sauaia, A. et al. "The Anatomy of an Article: The Discussion Section: "How Does the Article I Read Today Change What I Will Recommend to my Patients Tomorrow?” The Journal of Trauma and Acute Care Surgery 74 (June 2013): 1599-1602; Research Limitations & Future Research . Lund Research Ltd., 2012; Summary: Using it Wisely. The Writing Center. University of North Carolina; Schafer, Mickey S. Writing the Discussion. Writing in Psychology course syllabus. University of Florida; Yellin, Linda L. A Sociology Writer's Guide . Boston, MA: Allyn and Bacon, 2009.

Writing Tip

Don’t Over-Interpret the Results!

Interpretation is a subjective exercise. As such, you should always approach the selection and interpretation of your findings introspectively and to think critically about the possibility of judgmental biases unintentionally entering into discussions about the significance of your work. With this in mind, be careful that you do not read more into the findings than can be supported by the evidence you have gathered. Remember that the data are the data: nothing more, nothing less.

MacCoun, Robert J. "Biases in the Interpretation and Use of Research Results." Annual Review of Psychology 49 (February 1998): 259-287; Ward, Paulet al, editors. The Oxford Handbook of Expertise . Oxford, UK: Oxford University Press, 2018.

Another Writing Tip

Don't Write Two Results Sections!

One of the most common mistakes that you can make when discussing the results of your study is to present a superficial interpretation of the findings that more or less re-states the results section of your paper. Obviously, you must refer to your results when discussing them, but focus on the interpretation of those results and their significance in relation to the research problem, not the data itself.

Azar, Beth. "Discussing Your Findings." American Psychological Association gradPSYCH Magazine (January 2006).

Yet Another Writing Tip

Avoid Unwarranted Speculation!

The discussion section should remain focused on the findings of your study. For example, if the purpose of your research was to measure the impact of foreign aid on increasing access to education among disadvantaged children in Bangladesh, it would not be appropriate to speculate about how your findings might apply to populations in other countries without drawing from existing studies to support your claim or if analysis of other countries was not a part of your original research design. If you feel compelled to speculate, do so in the form of describing possible implications or explaining possible impacts. Be certain that you clearly identify your comments as speculation or as a suggestion for where further research is needed. Sometimes your professor will encourage you to expand your discussion of the results in this way, while others don’t care what your opinion is beyond your effort to interpret the data in relation to the research problem.

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Training videos | Faqs

Discussion Section Examples and Writing Tips

In this blog, we look at how to write the discussion section of a research paper. We will go through plenty of discussion examples and understand how to construct a great discussion section for your research paper.

1. What is the purpose of the discussion section?

The discussion section is one of the most important sections of your research paper. This is where you interpret your results, highlight your contributions, and explain the value of your work to your readers. This is one of the challenging parts to write because the author must clearly explain the significance of their results and tie everything back to the research questions.

2. How should I structure my discussion section?

Generally, the discussion section of a research paper typically contains the following parts.

Research summary It is a good idea to start this section with an overall summary of your work and highlight the main findings of your research.

Interpretation of findings You must interpret your findings clearly to your readers one by one.

Comparison with literature You must talk about how your results fit into existing research in the literature.

Implications of your work You should talk about the implications and possible benefits of your research.

Limitations You should talk about the possible limitations and shortcomings of your research

Future work And finally, you can talk about the possible future directions of your work.

3. Discussion Examples

Let’s look at some examples of the discussion section. We will be looking at discussion examples from different fields and of different formats. We have split this section into multiple components so that it is easy for you to digest and understand.

3.1. An example of research summary in discussion

It is a good idea to start your discussion section with the summary of your work. The best way to do this will be to restate your research question, and then reminding your readers about your methods, and finally providing an overall summary of your results.

Our aims were to compare the effectiveness and user-friendliness of different storm detection software for storm tracking. On the basis of these aims, we ran multiple experiments with the same conditions using different storm detection software. Our results showed that in both speed and accuracy of data, ‘software A’ performed better than ‘software B’. _ Aims summary _ Methodology summary _ Results summary

This discussion example is from an engineering research paper. The authors are restating their aims first, which is to compare different types of storm-tracking software. Then, they are providing a brief summary of the methods. Here, they are testing different storm-tracking software under different conditions to see which performs the best. Then, they are finally providing their main finding which is that they found ‘software A’ better than ‘software B’. This is a very good example of how to start the discussion section by presenting a summary of your work.

3.2. An example of result interpretation in discussion

The next step is to interpret your results. You have to explain your results clearly to your readers. Here is a discussion example that shows how to interpret your results.

The results of this study indicate significant differences between classical music and pop music in terms of their effects on memory recall and cognition. This implies that as the complexity of the music increases, so does its ability to facilitate cognitive processing. This finding aligns with the well-known “Mozart effect,” which suggests that listening to classical music can enhance cognitive function. _ Result _ Interpretation _ Additional evidence

The authors are saying that their results show that there is a significant difference between pop music and classical music in terms of memory recall and cognition. Now they are providing their interpretation of the findings. They think it is because there is a link between the complexity of music and cognitive processing. They are also making a reference to a well-known theory called the ‘Mozart effect’ to back up their findings. It is a nicely written passage and the author’s interpretation sounds very convincing and credible.

3.3. An example of literature comparison in discussion

The next step is to compare your results to the literature. You have to explain clearly how your findings compare with similar findings made by other researchers. Here is a discussion example where authors are providing details of papers in the literature that both support and oppose their findings.

Our analysis predicts that climate change will have a significant impact on wheat yield. This finding undermines one of the central pieces of evidence in some previous simulation studies [1-3] that suggest a negative effect of climate change on wheat yield, but the result is entirely consistent with the predictions of other research [4-5] that suggests the overall change in climate could result in increases in wheat yield. _ Result _ Comparison with literature

The authors are saying that their results show that climate change will have a significant effect on wheat production. Then, they are saying that there are some papers in the literature that are in agreement with their findings. However, there are also many papers in the literature that disagree with their findings. This is very important. Your discussion should be two-sided, not one-sided. You should not ignore the literature that doesn’t corroborate your findings.

3.4. An example of research implications in discussion

The next step is to explain to your readers how your findings will benefit society and the research community. You have to clearly explain the value of your work to your readers. Here is a discussion example where authors explain the implications of their research.

The results contribute insights with regard to the management of wildfire events using artificial intelligence. One could easily argue that the obvious practical implication of this study is that it proposes utilizing cloud-based machine vision to detect wildfires in real-time, even before the first responders receive emergency calls. _ Your finding _ Implications of your finding

In this paper, the authors are saying that their findings indicate that Artificial intelligence can be used to effectively manage wildfire events. Then, they are talking about the practical implications of their study. They are saying that their work has proven that machine learning can be used to detect wildfires in real-time. This is a great practical application and can save thousands of lives. As you can see, after reading this passage, you can immediately understand the value and significance of the work.

3.5. An example of limitations in discussion

It is very important that you discuss the limitations of your study. Limitations are flaws and shortcomings of your study. You have to tell your readers how your limitations might influence the outcomes and conclusions of your research. Most studies will have some form of limitation. So be honest and don’t hide your limitations. In reality, your readers and reviewers will be impressed with your paper if you are upfront about your limitations.

Study design and small sample size are important limitations. This could have led to an overestimation of the effect. Future research should reconfirm these findings by conducting larger-scale studies. _ Limitation _ How it might affect the results? _ How to fix the limitation?

Here is a discussion example where the author talks about study limitations. The authors are saying that the main limitations of the study are the small sample size and weak study design. Then they explain how this might have affected their results. They are saying that it is possible that they are overestimating the actual effect they are measuring. Then finally they are telling the readers that more studies with larger sample sizes should be conducted to reconfirm the findings.

As you can see, the authors are clearly explaining three things here:

3.6. An example of future work in discussion

It is important to remember not to end your paper with limitations. Finish your paper on a positive note by telling your readers about the benefits of your research and possible future directions. Here is a discussion example where the author talks about future work.

Our study highlights useful insights about the potential of biomass as a renewable energy source. Future research can extend this research in several ways, including research on how to tackle challenges that hinder the sustainability of renewable energy sources towards climate change mitigation, such as market failures, lack of information and access to raw materials. _ Benefits of your work _ Future work

The authors are starting the final paragraph of the discussion section by highlighting the benefit of their work which is the use of biomass as a renewable source of energy. Then they talk about future research. They are saying that future research can focus on how to improve the sustainability of biomass production. This is a very good example of how to finish the discussion section of your paper on a positive note.

4. Frequently Asked Questions

Sometimes you will have negative or unexpected results in your paper. You have to talk about it in your discussion section. A lot of students find it difficult to write this part. The best way to handle this situation is not to look at results as either positive or negative. A result is a result, and you will always have something important and interesting to say about your findings. Just spend some time investigating what might have caused this result and tell your readers about it.

You must talk about the limitations of your work in the discussion section of the paper. One of the important qualities that the scientific community expects from a researcher is honesty and admitting when they have made a mistake. The important trick you have to learn while presenting your limitations is to present them in a constructive way rather than being too negative about them. You must try to use positive language even when you are talking about major limitations of your work.

If you have something exciting to say about your results or found something new that nobody else has found before, then, don’t be modest and use flat language when presenting this in the discussion. Use words like ‘break through’, ‘indisputable evidence’, ‘exciting proposition’ to increase the impact of your findings.

Important thing to remember is not to overstate your findings. If you found something really interesting but are not 100% sure, you must not mislead your readers. The best way to do this will be to use words like ‘it appears’ and ‘it seems’. This will tell the readers that there is a slight possibility that you might be wrong.

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In this blog, we will go through many conclusion examples and learn how to present a powerful final take-home message to your readers.

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Writing a Medical Clinical Trial Research Paper – Example & Format

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Introduction Paragraph Examples and Writing Tips

In this blog, we will go through a few introduction paragraph examples and understand how to construct a great introduction paragraph for your research paper.

How to Create a Research Paper Outline?

In this blog we will see how to create a research paper outline and start writing your research paper.

Critical Literature Review : How to Critique a Research Article?

In this blog, we will look at how to use constructive language when critiquing other’s work in your research paper.

How to Write a Discussion Section for a Research Paper

We’ve talked about several useful writing tips that authors should consider while drafting or editing their research papers. In particular, we’ve focused on figures and legends , as well as the Introduction , Methods , and Results . Now that we’ve addressed the more technical portions of your journal manuscript, let’s turn to the analytical segments of your research article. In this article, we’ll provide tips on how to write a strong Discussion section that best portrays the significance of your research contributions.

What is the Discussion section of a research paper?

In a nutshell, your Discussion fulfills the promise you made to readers in your Introduction . At the beginning of your paper, you tell us why we should care about your research. You then guide us through a series of intricate images and graphs that capture all the relevant data you collected during your research. We may be dazzled and impressed at first, but none of that matters if you deliver an anti-climactic conclusion in the Discussion section!

Are you feeling pressured? Don’t worry. To be honest, you will edit the Discussion section of your manuscript numerous times. After all, in as little as one to two paragraphs ( Nature ‘s suggestion based on their 3,000-word main body text limit), you have to explain how your research moves us from point A (issues you raise in the Introduction) to point B (our new understanding of these matters). You must also recommend how we might get to point C (i.e., identify what you think is the next direction for research in this field). That’s a lot to say in two paragraphs!

So, how do you do that? Let’s take a closer look.

What should I include in the Discussion section?

As we stated above, the goal of your Discussion section is to answer the questions you raise in your Introduction by using the results you collected during your research . The content you include in the Discussions segment should include the following information:

Remind us why we should be interested in this research project.
Describe the nature of the knowledge gap you were trying to fill using the results of your study.
Don’t repeat your Introduction. Instead, focus on why this particular study was needed to fill the gap you noticed and why that gap needed filling in the first place.
Mainly, you want to remind us of how your research will increase our knowledge base and inspire others to conduct further research.
Clearly tell us what that piece of missing knowledge was.
Answer each of the questions you asked in your Introduction and explain how your results support those conclusions.
Make sure to factor in all results relevant to the questions (even if those results were not statistically significant).
Focus on the significance of the most noteworthy results.
If conflicting inferences can be drawn from your results, evaluate the merits of all of them.
Don’t rehash what you said earlier in the Results section. Rather, discuss your findings in the context of answering your hypothesis. Instead of making statements like “[The first result] was this…,” say, “[The first result] suggests [conclusion].”
Do your conclusions line up with existing literature?
Discuss whether your findings agree with current knowledge and expectations.
Keep in mind good persuasive argument skills, such as explaining the strengths of your arguments and highlighting the weaknesses of contrary opinions.
If you discovered something unexpected, offer reasons. If your conclusions aren’t aligned with current literature, explain.
Address any limitations of your study and how relevant they are to interpreting your results and validating your findings.
Make sure to acknowledge any weaknesses in your conclusions and suggest room for further research concerning that aspect of your analysis.
Make sure your suggestions aren’t ones that should have been conducted during your research! Doing so might raise questions about your initial research design and protocols.
Similarly, maintain a critical but unapologetic tone. You want to instill confidence in your readers that you have thoroughly examined your results and have objectively assessed them in a way that would benefit the scientific community’s desire to expand our knowledge base.
Recommend next steps.
Your suggestions should inspire other researchers to conduct follow-up studies to build upon the knowledge you have shared with them.
Keep the list short (no more than two).

How to Write the Discussion Section

The above list of what to include in the Discussion section gives an overall idea of what you need to focus on throughout the section. Below are some tips and general suggestions about the technical aspects of writing and organization that you might find useful as you draft or revise the contents we’ve outlined above.

Technical writing elements

Embrace active voice because it eliminates the awkward phrasing and wordiness that accompanies passive voice.
Use the present tense, which should also be employed in the Introduction.
Sprinkle with first person pronouns if needed, but generally, avoid it. We want to focus on your findings.
Maintain an objective and analytical tone.

Discussion section organization

Keep the same flow across the Results, Methods, and Discussion sections.
We develop a rhythm as we read and parallel structures facilitate our comprehension. When you organize information the same way in each of these related parts of your journal manuscript, we can quickly see how a certain result was interpreted and quickly verify the particular methods used to produce that result.
Notice how using parallel structure will eliminate extra narration in the Discussion part since we can anticipate the flow of your ideas based on what we read in the Results segment. Reducing wordiness is important when you only have a few paragraphs to devote to the Discussion section!
Within each subpart of a Discussion, the information should flow as follows: (A) conclusion first, (B) relevant results and how they relate to that conclusion and (C) relevant literature.
End with a concise summary explaining the big-picture impact of your study on our understanding of the subject matter. At the beginning of your Discussion section, you stated why this particular study was needed to fill the gap you noticed and why that gap needed filling in the first place. Now, it is time to end with “how your research filled that gap.”

Discussion Part 1: Summarizing Key Findings

Begin the Discussion section by restating your statement of the problem and briefly summarizing the major results. Do not simply repeat your findings. Rather, try to create a concise statement of the main results that directly answer the central research question that you stated in the Introduction section . This content should not be longer than one paragraph in length.

Many researchers struggle with understanding the precise differences between a Discussion section and a Results section . The most important thing to remember here is that your Discussion section should subjectively evaluate the findings presented in the Results section, and in relatively the same order. Keep these sections distinct by making sure that you do not repeat the findings without providing an interpretation.

Phrase examples: Summarizing the results

The findings indicate that …
These results suggest a correlation between A and B …
The data present here suggest that …
An interpretation of the findings reveals a connection between…

Discussion Part 2: Interpreting the Findings

What do the results mean? It may seem obvious to you, but simply looking at the figures in the Results section will not necessarily convey to readers the importance of the findings in answering your research questions.

The exact structure of interpretations depends on the type of research being conducted. Here are some common approaches to interpreting data:

Identifying correlations and relationships in the findings
Explaining whether the results confirm or undermine your research hypothesis
Giving the findings context within the history of similar research studies
Discussing unexpected results and analyzing their significance to your study or general research
Offering alternative explanations and arguing for your position

Organize the Discussion section around key arguments, themes, hypotheses, or research questions or problems. Again, make sure to follow the same order as you did in the Results section.

Discussion Part 3: Discussing the Implications

In addition to providing your own interpretations, show how your results fit into the wider scholarly literature you surveyed in the literature review section. This section is called the implications of the study . Show where and how these results fit into existing knowledge, what additional insights they contribute, and any possible consequences that might arise from this knowledge, both in the specific research topic and in the wider scientific domain.

Questions to ask yourself when dealing with potential implications:

Do your findings fall in line with existing theories, or do they challenge these theories or findings? What new information do they contribute to the literature, if any? How exactly do these findings impact or conflict with existing theories or models?
What are the practical implications on actual subjects or demographics?
What are the methodological implications for similar studies conducted either in the past or future?

Your purpose in giving the implications is to spell out exactly what your study has contributed and why researchers and other readers should be interested.

Phrase examples: Discussing the implications of the research

These results confirm the existing evidence in X studies…
The results are not in line with the foregoing theory that…
This experiment provides new insights into the connection between…
These findings present a more nuanced understanding of…
While previous studies have focused on X, these results demonstrate that Y.

Step 4: Acknowledging the limitations

All research has study limitations of one sort or another. Acknowledging limitations in methodology or approach helps strengthen your credibility as a researcher. Study limitations are not simply a list of mistakes made in the study. Rather, limitations help provide a more detailed picture of what can or cannot be concluded from your findings. In essence, they help temper and qualify the study implications you listed previously.

Study limitations can relate to research design, specific methodological or material choices, or unexpected issues that emerged while you conducted the research. Mention only those limitations directly relate to your research questions, and explain what impact these limitations had on how your study was conducted and the validity of any interpretations.

Possible types of study limitations:

Insufficient sample size for statistical measurements
Lack of previous research studies on the topic
Methods/instruments/techniques used to collect the data
Limited access to data
Time constraints in properly preparing and executing the study

After discussing the study limitations, you can also stress that your results are still valid. Give some specific reasons why the limitations do not necessarily handicap your study or narrow its scope.

Phrase examples: Limitations sentence beginners

“There may be some possible limitations in this study.”
“The findings of this study have to be seen in light of some limitations.”
“The first limitation is the…The second limitation concerns the…”
“The empirical results reported herein should be considered in the light of some limitations.”
“This research, however, is subject to several limitations.”
“The primary limitation to the generalization of these results is…”
“Nonetheless, these results must be interpreted with caution and a number of limitations should be borne in mind.”

Discussion Part 5: Giving Recommendations for Further Research

Based on your interpretation and discussion of the findings, your recommendations can include practical changes to the study or specific further research to be conducted to clarify the research questions. Recommendations are often listed in a separate Conclusion section , but often this is just the final paragraph of the Discussion section.

Suggestions for further research often stem directly from the limitations outlined. Rather than simply stating that “further research should be conducted,” provide concrete specifics for how future can help answer questions that your research could not.

Phrase examples: Recommendation sentence beginners

Further research is needed to establish …
There is abundant space for further progress in analyzing…
A further study with more focus on X should be done to investigate…
Further studies of X that account for these variables must be undertaken.

Consider Receiving Professional Language Editing

As you edit or draft your research manuscript, we hope that you implement these guidelines to produce a more effective Discussion section. And after completing your draft, don’t forget to submit your work to a professional proofreading and English editing service like Wordvice, including our manuscript editing service for paper editing , cover letter editing , SOP editing , and personal statement proofreading services. Language editors not only proofread and correct errors in grammar, punctuation, mechanics, and formatting but also improve terms and revise phrases so they read more naturally. Wordvice is an industry leader in providing high-quality revision for all types of academic documents.

For additional information about how to write a strong research paper, make sure to check out our full research writing series !

Wordvice Writing Resources

How to Write a Research Paper Introduction
Which Verb Tenses to Use in a Research Paper
How to Write an Abstract for a Research Paper
How to Write a Research Paper Title
Useful Phrases for Academic Writing
Common Transition Terms in Academic Papers
Active and Passive Voice in Research Papers
100+ Verbs That Will Make Your Research Writing Amazing
Tips for Paraphrasing in Research Papers

Additional Academic Resources

Guide for Authors. (Elsevier)
How to Write the Results Section of a Research Paper. (Bates College)
Structure of a Research Paper. (University of Minnesota Biomedical Library)
How to Choose a Target Journal (Springer)
How to Write Figures and Tables (UNC Writing Center)

How to Write the Discussion Section of a Research Paper

The discussion section of a research paper analyzes and interprets the findings, provides context, compares them with previous studies, identifies limitations, and suggests future research directions.

Updated on September 15, 2023

researchers writing the discussion section of their research paper

Structure your discussion section right, and you’ll be cited more often while doing a greater service to the scientific community. So, what actually goes into the discussion section? And how do you write it?

The discussion section of your research paper is where you let the reader know how your study is positioned in the literature, what to take away from your paper, and how your work helps them. It can also include your conclusions and suggestions for future studies.

First, we’ll define all the parts of your discussion paper, and then look into how to write a strong, effective discussion section for your paper or manuscript.

Discussion section: what is it, what it does

The discussion section comes later in your paper, following the introduction, methods, and results. The discussion sets up your study’s conclusions. Its main goals are to present, interpret, and provide a context for your results.

What is it?

The discussion section provides an analysis and interpretation of the findings, compares them with previous studies, identifies limitations, and suggests future directions for research.

This section combines information from the preceding parts of your paper into a coherent story. By this point, the reader already knows why you did your study (introduction), how you did it (methods), and what happened (results). In the discussion, you’ll help the reader connect the ideas from these sections.

Why is it necessary?

The discussion provides context and interpretations for the results. It also answers the questions posed in the introduction. While the results section describes your findings, the discussion explains what they say. This is also where you can describe the impact or implications of your research.

Adds context for your results

Most research studies aim to answer a question, replicate a finding, or address limitations in the literature. These goals are first described in the introduction. However, in the discussion section, the author can refer back to them to explain how the study's objective was achieved.

Shows what your results actually mean and real-world implications

The discussion can also describe the effect of your findings on research or practice. How are your results significant for readers, other researchers, or policymakers?

What to include in your discussion (in the correct order)

A complete and effective discussion section should at least touch on the points described below.

Summary of key findings

The discussion should begin with a brief factual summary of the results. Concisely overview the main results you obtained.

Begin with key findings with supporting evidence

Your results section described a list of findings, but what message do they send when you look at them all together?

Your findings were detailed in the results section, so there’s no need to repeat them here, but do provide at least a few highlights. This will help refresh the reader’s memory and help them focus on the big picture.

Read the first paragraph of the discussion section in this article (PDF) for an example of how to start this part of your paper. Notice how the authors break down their results and follow each description sentence with an explanation of why each finding is relevant.

State clearly and concisely

Following a clear and direct writing style is especially important in the discussion section. After all, this is where you will make some of the most impactful points in your paper. While the results section often contains technical vocabulary, such as statistical terms, the discussion section lets you describe your findings more clearly.

Interpretation of results

Once you’ve given your reader an overview of your results, you need to interpret those results. In other words, what do your results mean? Discuss the findings’ implications and significance in relation to your research question or hypothesis.

Analyze and interpret your findings

Look into your findings and explore what’s behind them or what may have caused them. If your introduction cited theories or studies that could explain your findings, use these sources as a basis to discuss your results.

For example, look at the second paragraph in the discussion section of this article on waggling honey bees. Here, the authors explore their results based on information from the literature.

Unexpected or contradictory results

Sometimes, your findings are not what you expect. Here’s where you describe this and try to find a reason for it. Could it be because of the method you used? Does it have something to do with the variables analyzed? Comparing your methods with those of other similar studies can help with this task.

Context and comparison with previous work

Refer to related studies to place your research in a larger context and the literature. Compare and contrast your findings with existing literature, highlighting similarities, differences, and/or contradictions.

How your work compares or contrasts with previous work

Studies with similar findings to yours can be cited to show the strength of your findings. Information from these studies can also be used to help explain your results. Differences between your findings and others in the literature can also be discussed here.

How to divide this section into subsections

If you have more than one objective in your study or many key findings, you can dedicate a separate section to each of these. Here’s an example of this approach. You can see that the discussion section is divided into topics and even has a separate heading for each of them.

Limitations

Many journals require you to include the limitations of your study in the discussion. Even if they don’t, there are good reasons to mention these in your paper.

Why limitations don’t have a negative connotation

A study’s limitations are points to be improved upon in future research. While some of these may be flaws in your method, many may be due to factors you couldn’t predict.

Examples include time constraints or small sample sizes. Pointing this out will help future researchers avoid or address these issues. This part of the discussion can also include any attempts you have made to reduce the impact of these limitations, as in this study .

How limitations add to a researcher's credibility

Pointing out the limitations of your study demonstrates transparency. It also shows that you know your methods well and can conduct a critical assessment of them.

Implications and significance

The final paragraph of the discussion section should contain the take-home messages for your study. It can also cite the “strong points” of your study, to contrast with the limitations section.

Restate your hypothesis

Remind the reader what your hypothesis was before you conducted the study.

How was it proven or disproven?

Identify your main findings and describe how they relate to your hypothesis.

How your results contribute to the literature

Were you able to answer your research question? Or address a gap in the literature?

Future implications of your research

Describe the impact that your results may have on the topic of study. Your results may show, for instance, that there are still limitations in the literature for future studies to address. There may be a need for studies that extend your findings in a specific way. You also may need additional research to corroborate your findings.

Sample discussion section

This fictitious example covers all the aspects discussed above. Your actual discussion section will probably be much longer, but you can read this to get an idea of everything your discussion should cover.

Our results showed that the presence of cats in a household is associated with higher levels of perceived happiness by its human occupants. These findings support our hypothesis and demonstrate the association between pet ownership and well-being.

The present findings align with those of Bao and Schreer (2016) and Hardie et al. (2023), who observed greater life satisfaction in pet owners relative to non-owners. Although the present study did not directly evaluate life satisfaction, this factor may explain the association between happiness and cat ownership observed in our sample.

Our findings must be interpreted in light of some limitations, such as the focus on cat ownership only rather than pets as a whole. This may limit the generalizability of our results.

Nevertheless, this study had several strengths. These include its strict exclusion criteria and use of a standardized assessment instrument to investigate the relationships between pets and owners. These attributes bolster the accuracy of our results and reduce the influence of confounding factors, increasing the strength of our conclusions. Future studies may examine the factors that mediate the association between pet ownership and happiness to better comprehend this phenomenon.

This brief discussion begins with a quick summary of the results and hypothesis. The next paragraph cites previous research and compares its findings to those of this study. Information from previous studies is also used to help interpret the findings. After discussing the results of the study, some limitations are pointed out. The paper also explains why these limitations may influence the interpretation of results. Then, final conclusions are drawn based on the study, and directions for future research are suggested.

How to make your discussion flow naturally

If you find writing in scientific English challenging, the discussion and conclusions are often the hardest parts of the paper to write. That’s because you’re not just listing up studies, methods, and outcomes. You’re actually expressing your thoughts and interpretations in words.

How formal should it be?
What words should you use, or not use?
How do you meet strict word limits, or make it longer and more informative?

Always give it your best, but sometimes a helping hand can, well, help. Getting a professional edit can help clarify your work’s importance while improving the English used to explain it. When readers know the value of your work, they’ll cite it. We’ll assign your study to an expert editor knowledgeable in your area of research. Their work will clarify your discussion, helping it to tell your story. Find out more about AJE Editing.

Adam Goulston, PsyD, MS, MBA, MISD, ELS

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Turk J Urol
v.39(Suppl 1); 2013 Sep

How to write a discussion section?

Writing manuscripts to describe study outcomes, although not easy, is the main task of an academician. The aim of the present review is to outline the main aspects of writing the discussion section of a manuscript. Additionally, we address various issues regarding manuscripts in general. It is advisable to work on a manuscript regularly to avoid losing familiarity with the article. On principle, simple, clear and effective language should be used throughout the text. In addition, a pre-peer review process is recommended to obtain feedback on the manuscript. The discussion section can be written in 3 parts: an introductory paragraph, intermediate paragraphs and a conclusion paragraph. For intermediate paragraphs, a “divide and conquer” approach, meaning a full paragraph describing each of the study endpoints, can be used. In conclusion, academic writing is similar to other skills, and practice makes perfect.

Introduction

Sharing knowledge produced during academic life is achieved through writing manuscripts. However writing manuscripts is a challenging endeavour in that we physicians have a heavy workload, and English which is common language used for the dissemination of scientific knowledge is not our mother tongue.

The objective of this review is to summarize the method of writing ‘Discussion’ section which is the most important, but probably at the same time the most unlikable part of a manuscript, and demonstrate the easy ways we applied in our practice, and finally share the frequently made relevant mistakes. During this procedure, inevitably some issues which concerns general concept of manuscript writing process are dealt with. Therefore in this review we will deal with topics related to the general aspects of manuscript writing process, and specifically issues concerning only the ‘Discussion’ section.

A) Approaches to general aspects of manuscript writing process:

1. what should be the strategy of sparing time for manuscript writing be.

Two different approaches can be formulated on this issue? One of them is to allocate at least 30 minutes a day for writing a manuscript which amounts to 3.5 hours a week. This period of time is adequate for completion of a manuscript within a few weeks which can be generally considered as a long time interval. Fundamental advantage of this approach is to gain a habit of making academic researches if one complies with the designated time schedule, and to keep the manuscript writing motivation at persistently high levels. Another approach concerning this issue is to accomplish manuscript writing process within a week. With the latter approach, the target is rapidly attained. However longer time periods spent in order to concentrate on the subject matter can be boring, and lead to loss of motivation. Daily working requirements unrelated to the manuscript writing might intervene, and prolong manuscript writing process. Alienation periods can cause loss of time because of need for recurrent literature reviews. The most optimal approach to manuscript writing process is daily writing strategy where higher levels of motivation are persistently maintained.

Especially before writing the manuscript, the most important step at the start is to construct a draft, and completion of the manuscript on a theoretical basis. Therefore, during construction of a draft, attention distracting environment should be avoided, and this step should be completed within 1–2 hours. On the other hand, manuscript writing process should begin before the completion of the study (even the during project stage). The justification of this approach is to see the missing aspects of the study and the manuscript writing methodology, and try to solve the relevant problems before completion of the study. Generally, after completion of the study, it is very difficult to solve the problems which might be discerned during the writing process. Herein, at least drafts of the ‘Introduction’, and ‘Material and Methods’ can be written, and even tables containing numerical data can be constructed. These tables can be written down in the ‘Results’ section. [ 1 ]

2. How should the manuscript be written?

The most important principle to be remembered on this issue is to obey the criteria of simplicity, clarity, and effectiveness. [ 2 ] Herein, do not forget that, the objective should be to share our findings with the readers in an easily comprehensible format. Our approach on this subject is to write all structured parts of the manuscript at the same time, and start writing the manuscript while reading the first literature. Thus newly arisen connotations, and self-brain gyms will be promptly written down. However during this process your outcomes should be revealed fully, and roughly the message of the manuscript which be delivered. Thus with this so-called ‘hunter’s approach’ the target can be achieved directly, and rapidly. Another approach is ‘collectioner’s approach. [ 3 ] In this approach, firstly, potential data, and literature studies are gathered, read, and then selected ones are used. Since this approach suits with surgical point of view, probably ‘hunter’s approach’ serves our purposes more appropriately. However, in parallel with academic development, our novice colleague ‘manuscripters’ can prefer ‘collectioner’s approach.’

On the other hand, we think that research team consisting of different age groups has some advantages. Indeed young colleagues have the enthusiasm, and energy required for the conduction of the study, while middle-aged researchers have the knowledge to manage the research, and manuscript writing. Experienced researchers make guiding contributions to the manuscript. However working together in harmony requires assignment of a chief researcher, and periodically organizing advancement meetings. Besides, talents, skills, and experiences of the researchers in different fields (ie. research methods, contact with patients, preparation of a project, fund-raising, statistical analysis etc.) will determine task sharing, and make a favourable contribution to the perfection of the manuscript. Achievement of the shared duties within a predetermined time frame will sustain the motivation of the researchers, and prevent wearing out of updated data.

According to our point of view, ‘Abstract’ section of the manuscript should be written after completion of the manuscript. The reason for this is that during writing process of the main text, the significant study outcomes might become insignificant or vice versa. However, generally, before onset of the writing process of the manuscript, its abstract might be already presented in various congresses. During writing process, this abstract might be a useful guide which prevents deviation from the main objective of the manuscript.

On the other hand references should be promptly put in place while writing the manuscript, Sorting, and placement of the references should not be left to the last moment. Indeed, it might be very difficult to remember relevant references to be placed in the ‘Discussion’ section. For the placement of references use of software programs detailed in other sections is a rational approach.

3. Which target journal should be selected?

In essence, the methodology to be followed in writing the ‘Discussion’ section is directly related to the selection of the target journal. Indeed, in compliance with the writing rules of the target journal, limitations made on the number of words after onset of the writing process, effects mostly the ‘Discussion’ section. Proper matching of the manuscript with the appropriate journal requires clear, and complete comprehension of the available data from scientific point of view. Previously, similar articles might have been published, however innovative messages, and new perspectives on the relevant subject will facilitate acceptance of the article for publication. Nowadays, articles questioning available information, rather than confirmatory ones attract attention. However during this process, classical information should not be questioned except for special circumstances. For example manuscripts which lead to the conclusions as “laparoscopic surgery is more painful than open surgery” or “laparoscopic surgery can be performed without prior training” will not be accepted or they will be returned by the editor of the target journal to the authors with the request of critical review. Besides the target journal to be selected should be ready to accept articles with similar concept. In fact editors of the journal will not reserve the limited space in their journal for articles yielding similar conclusions.

The title of the manuscript is as important as the structured sections * of the manuscript. The title can be the most striking or the newest outcome among results obtained.

Before writing down the manuscript, determination of 2–3 titles increases the motivation of the authors towards the manuscript. During writing process of the manuscript one of these can be selected based on the intensity of the discussion. However the suitability of the title to the agenda of the target journal should be investigated beforehand. For example an article bearing the title “Use of barbed sutures in laparoscopic partial nephrectomy shortens warm ischemia time” should not be sent to “Original Investigations and Seminars in Urologic Oncology” Indeed the topic of the manuscript is out of the agenda of this journal.

4. Do we have to get a pre-peer review about the written manuscript?

Before submission of the manuscript to the target journal the opinions of internal, and external referees should be taken. [ 1 ] Internal referees can be considered in 2 categories as “General internal referees” and “expert internal referees” General internal referees (ie. our colleagues from other medical disciplines) are not directly concerned with your subject matter but as mentioned above they critically review the manuscript as for simplicity, clarity, and effectiveness of its writing style. Expert internal reviewers have a profound knowledge about the subject, and they can provide guidance about the writing process of the manuscript (ie. our senior colleagues more experienced than us). External referees are our colleagues who did not contribute to data collection of our study in any way, but we can request their opinions about the subject matter of the manuscript. Since they are unrelated both to the author(s), and subject matter of the manuscript, these referees can review our manuscript more objectively. Before sending the manuscript to internal, and external referees, we should contact with them, and ask them if they have time to review our manuscript. We should also give information about our subject matter. Otherwise pre-peer review process can delay publication of the manuscript, and decrease motivation of the authors. In conclusion, whoever the preferred referee will be, these internal, and external referees should respond the following questions objectively. 1) Does the manuscript contribute to the literature?; 2) Does it persuasive? 3) Is it suitable for the publication in the selected journal? 4) Has a simple, clear, and effective language been used throughout the manuscript? In line with the opinions of the referees, the manuscript can be critically reviewed, and perfected. [ 1 ]**

Following receival of the opinions of internal, and external referees, one should concentrate priorly on indicated problems, and their solutions. Comments coming from the reviewers should be criticized, but a defensive attitude should not be assumed during this evaluation process. During this “incubation” period where the comments of the internal, and external referees are awaited, literature should be reviewed once more. Indeed during this time interval a new article which you should consider in the ‘Discussion’ section can be cited in the literature.

5. What are the common mistakes made related to the writing process of a manuscript?

Probably the most important mistakes made related to the writing process of a manuscript include lack of a clear message of the manuscript , inclusion of more than one main idea in the same text or provision of numerous unrelated results at the same time so as to reinforce the assertions of the manuscript. This approach can be termed roughly as “loss of the focus of the study” In conclusion, the author(s) should ask themselves the following question at every stage of the writing process:. “What is the objective of the study? If you always get clear-cut answers whenever you ask this question, then the study is proceeding towards the right direction. Besides application of a template which contains the intended clear-cut messages to be followed will contribute to the communication of net messages.

One of the important mistakes is refraining from critical review of the manuscript as a whole after completion of the writing process. Therefore, the authors should go over the manuscript for at least three times after finalization of the manuscript based on joint decision. The first control should concentrate on the evaluation of the appropriateness of the logic of the manuscript, and its organization, and whether desired messages have been delivered or not. Secondly, syutax, and grammar of the manuscript should be controlled. It is appropriate to review the manuscript for the third time 1 or 2 weeks after completion of its writing process. Thus, evaluation of the “cooled” manuscript will be made from a more objective perspective, and assessment process of its integrity will be facilitated.

Other erroneous issues consist of superfluousness of the manuscript with unnecessary repetitions, undue, and recurrent references to the problems adressed in the manuscript or their solution methods, overcriticizing or overpraising other studies, and use of a pompous literary language overlooking the main objective of sharing information. [ 4 ]

B) Approaches to the writing process of the ‘Discussion’ section:

1. how should the main points of ‘discussion’ section be constructed.

Generally the length of the ‘Discussion ‘ section should not exceed the sum of other sections (ıntroduction, material and methods, and results), and it should be completed within 6–7 paragraphs.. Each paragraph should not contain more than 200 words, and hence words should be counted repeteadly. The ‘Discussion’ section can be generally divided into 3 separate paragraphs as. 1) Introductory paragraph, 2) Intermediate paragraphs, 3) Concluding paragraph.

The introductory paragraph contains the main idea of performing the study in question. Without repeating ‘Introduction’ section of the manuscript, the problem to be addressed, and its updateness are analysed. The introductory paragraph starts with an undebatable sentence, and proceeds with a part addressing the following questions as 1) On what issue we have to concentrate, discuss or elaborate? 2) What solutions can be recommended to solve this problem? 3) What will be the new, different, and innovative issue? 4) How will our study contribute to the solution of this problem An introductory paragraph in this format is helpful to accomodate reader to the rest of the Discussion section. However summarizing the basic findings of the experimental studies in the first paragraph is generally recommended by the editors of the journal. [ 5 ]

In the last paragraph of the Discussion section “strong points” of the study should be mentioned using “constrained”, and “not too strongly assertive” statements. Indicating limitations of the study will reflect objectivity of the authors, and provide answers to the questions which will be directed by the reviewers of the journal. On the other hand in the last paragraph, future directions or potential clinical applications may be emphasized.

2. How should the intermediate paragraphs of the Discussion section be formulated?

The reader passes through a test of boredom while reading paragraphs of the Discussion section apart from the introductory, and the last paragraphs. Herein your findings rather than those of the other researchers are discussed. The previous studies can be an explanation or reinforcement of your findings. Each paragraph should contain opinions in favour or against the topic discussed, critical evaluations, and learning points.

Our management approach for intermediate paragraphs is “divide and conquer” tactics. Accordingly, the findings of the study are determined in order of their importance, and a paragraph is constructed for each finding ( Figure 1 ). Each paragraph begins with an “indisputable” introductory sentence about the topic to be discussed. This sentence basically can be the answer to the question “What have we found?” Then a sentence associated with the subject matter to be discussed is written. Subsequently, in the light of the current literature this finding is discussed, new ideas on this subject are revealed, and the paragraph ends with a concluding remark.

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Divide and Conquer tactics

In this paragraph, main topic should be emphasized without going into much detail. Its place, and importance among other studies should be indicated. However during this procedure studies should be presented in a logical sequence (ie. from past to present, from a few to many cases), and aspects of the study contradictory to other studies should be underlined. Results without any supportive evidence or equivocal results should not be written. Besides numerical values presented in the Results section should not be repeated unless required.

Besides, asking the following questions, and searching their answers in the same paragraph will facilitate writing process of the paragraph. [ 1 ] 1) Can the discussed result be false or inadequate? 2) Why is it false? (inadequate blinding, protocol contamination, lost to follow-up, lower statistical power of the study etc.), 3) What meaning does this outcome convey?

3. What are the common mistakes made in writing the Discussion section?:

Probably the most important mistake made while writing the Discussion section is the need for mentioning all literature references. One point to remember is that we are not writing a review article, and only the results related to this paragraph should be discussed. Meanwhile, each word of the paragraphs should be counted, and placed carefully. Each word whose removal will not change the meaning should be taken out from the text.” Writing a saga with “word salads” *** is one of the reasons for prompt rejection. Indeed, if the reviewer thinks that it is difficult to correct the Discussion section, he/she use her/ his vote in the direction of rejection to save time (Uniform requirements for manuscripts: International Comittee of Medical Journal Editors [ http://www.icmje.org/urm_full.pdf ])

The other important mistake is to give too much references, and irrelevancy between the references, and the section with these cited references. [ 3 ] While referring these studies, (excl. introductory sentences linking indisputable sentences or paragraphs) original articles should be cited. Abstracts should not be referred, and review articles should not be cited unless required very much.

4. What points should be paid attention about writing rules, and grammar?

As is the case with the whole article, text of the Discussion section should be written with a simple language, as if we are talking with our colleague. [ 2 ] Each sentence should indicate a single point, and it should not exceed 25–30 words. The priorly mentioned information which linked the previous sentence should be placed at the beginning of the sentence, while the new information should be located at the end of the sentence. During construction of the sentences, avoid unnecessary words, and active voice rather than passive voice should be used.**** Since conventionally passive voice is used in the scientific manuscripts written in the Turkish language, the above statement contradicts our writing habits. However, one should not refrain from beginning the sentences with the word “we”. Indeed, editors of the journal recommend use of active voice so as to increase the intelligibility of the manuscript.

In conclusion, the major point to remember is that the manuscript should be written complying with principles of simplicity, clarity, and effectiveness. In the light of these principles, as is the case in our daily practice, all components of the manuscript (IMRAD) can be written concurrently. In the ‘Discussion’ section ‘divide and conquer’ tactics remarkably facilitates writing process of the discussion. On the other hand, relevant or irrelevant feedbacks received from our colleagues can contribute to the perfection of the manuscript. Do not forget that none of the manuscripts is perfect, and one should not refrain from writing because of language problems, and related lack of experience.

Instead of structured sections of a manuscript (IMRAD): Introduction, Material and Methods, Results, and Discussion

Instead of in the Istanbul University Faculty of Medicine posters to be submitted in congresses are time to time discussed in Wednesday meetings, and opinions of the internal referees are obtained about the weak, and strong points of the study

Instead of a writing style which uses words or sentences with a weak logical meaning that do not lead the reader to any conclusion

Instead of “white color”; “proven”; nstead of “history”; “to”. should be used instead of “white in color”, “definitely proven”, “past history”, and “in order to”, respectively ( ref. 2 )

Instead of “No instances of either postoperative death or major complications occurred during the early post-operative period” use “There were no deaths or major complications occurred during the early post-operative period.

Instead of “Measurements were performed to evaluate the levels of CEA in the serum” use “We measured serum CEA levels”

Research Paper Writing Guides

Research Paper Discussion Section

Last updated on: Mar 27, 2024

A Detailed Guide: How to Write a Discussion for a Research Paper

By: Jared P.

11 min read

Reviewed By:

Published on: Mar 6, 2024

how to write a discussion for a research paper

Writing a research paper discussion isn’t something everyone is good at. You have to portray the significance of your research in the best possible way. If you’re having a hard time writing a convincing discussion, don’t worry!

In this guide, we’ll discuss how to write a research paper discussion. From understanding its importance, elements, writing steps, and some examples, we have it covered.

Continue reading, and you’ll be more than able to discuss your research paper effectively.

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What is a Research Paper Discussion?

A research paper discussion informs the reader about the learning outcomes of the research study. Here, the author provides context for the results by explaining how they relate to existing literature, theories, and the overall body of knowledge in the field.

The discussion answers the questions you raised in the introduction by utilizing the results and findings gathered in the study.

Where to Place the Discussion Section?

The optimal place for the discussion is to write it after the research paper introduction and before the conclusion for a research paper. It is not a hard and fast rule to sum up your discussion in a single paragraph. You can utilize 2 or at max 3 paragraphs or a convincing discussion.

Understanding the Importance of a Good Discussion Section

Here’s why the discussion is one of the most significant sections of your research paper.

Connects the Dots: The discussion links back to the questions raised in the introduction, showing how your study answers them.
Engages with Experts: It places your study in a conversation with what smart people have said about the research paper topic, creating a connection to existing research.
Guides the Reader: Think of it as a roadmap, pointing the way to the next stop in research and leaving readers at the start of new possibilities.
Adds Meaning: It's not just a conclusion; it's the key to unlocking the meaning behind your findings, helping readers understand why your study is important.
Highlights Significance: Demonstrates the significance of your study by explaining its impact on the reader's understanding of the research paper problem statement .
Encourages Thinking: The discussion makes readers speculate more about why your study matters, helping them see the bigger picture.
Keeps the Conversation Going: It suggests new questions or areas to explore, so the study isn't just an endpoint but a starting point for more research.

Read on to see what key elements make up a great discussion.

Key Components of a Research Paper Discussion

There are multiple ways to write the discussion section, but usually, it revolves around the following key elements.

Interpretation of Results

Explains the meaning of your findings and how they address the research questions or the research paper hypotheses .

Comparison With Previous Studies

Discusses how your study and research findings align with or differ from previous studies in the field.

Theoretical Implications

Explores the theoretical significance of your findings and their contribution to existing theories.

Practical implications

Discusses the real-world applications or implications of your research.

Limitations

Acknowledges any limitations in your study that may affect the interpretation of results.

Suggestions for Future Research

Proposes directions for future research and highlights areas that need further exploration.

Integration of Your Research Findings

Summarizes the key points discussed in the discussion section and restate the main conclusions drawn from the study.

After understanding the essential elements that make up the discussion section, you need to know how to combine them for a stellar discussion.

So, let’s move on to the writing steps.

How to Write a Discussion for a Research Paper in 6 Easy Steps

Follow these steps for writing a good research paper discussion section.

Summarize Findings: Begin with a concise summary of your main results.
Interpret Results: Interpret and explain the meaning of your findings.
Compare with Literature: Compare your results to existing literature.
Discuss Implications: Explore theoretical and practical implications.
Acknowledge Limitations: Clearly state and discuss the limitations of your study.
Propose Future Research: Suggest directions for future research.

Here is a detailed breakdown of each writing step.

Step 1. Summarize Your Findings

Begin this section by summarizing the key discoveries in your study. In a nutshell, tell your readers what you found, avoiding a repetition of raw data. Aim for clarity, condensing the main results into a brief paragraph.

You can start your summary with the following sentences:

In this study, the key findings indicate...
To distill the results, it is evident that...
Summarizing our main discoveries, we observe...

Example:

Step 2. Interpret Results and Your Findings

Move on to interpreting what your findings truly mean. Don't assume your readers will automatically understand the significance. Provide your insights and explanations, considering how the results align with your research question or research paper hypothesis.

You can start interpreting your results with the following sentences:

Interpreting these results, it becomes clear that...
These findings imply that...
Exploring the meaning behind the data, we can infer that...

Step 3. Compare With Existing Literature

Connect your results to existing knowledge and previous research by comparing them with what other researchers have discovered. Show where your study fits into the broader context of the literature, and highlight any differences or similarities.

You can compare your research with existing literature by incorporating the following sentences:

Aligning our results with existing literature, we find...
Comparing our study to prior research, a parallel emerges...
In relation to the broader scholarly conversation, our results resonate with...

Step 4. Discuss Implications of Your Research

Explore both the theoretical and practical implications of your research. Explain how your findings contribute to existing theories and discuss any real-world applications. Clarify why your study matters in a larger context.

You can start discussing your implication with the following sentences:

Considering the implications of our study, it becomes apparent that...
Beyond the theoretical implications, our findings hold practical significance by...
Exploring the broader impact, our research suggests...

Step 5. Acknowledge the Limitations

Be transparent about the shortcomings of your study. Discuss any constraints in your research design, research paper methods , or unexpected challenges. This not only showcases your honesty but also helps readers understand the scope of your study.

Here are some limitation sentence starters:

While our study contributes valuable insights, it's essential to acknowledge...
Recognizing the constraints of our research, one limitation is...
Despite the valuable findings, it's important to note the limitations, including...

Step 6. Propose Future Research

Wrap up by proposing directions for future research. Point out areas that need further exploration or refinement based on the gaps identified in your study. Provide a launchpad for future researchers to build upon your work.

Here are some future research sentence starters:

This study sets the stage for future research by...
To build upon this groundwork, future studies could...
Exploring uncharted territory, future research might investigate...

In only 6 steps, you can craft research paper discussions that can convince readers that your study stands out from the rest and that it contributes to the specific field of research effectively.

Having said that, it is important to keep note of some common mistakes that you might make in the writing process. Let’s see what you should avoid in your research paper discussion.

Avoiding Common Mistakes in Research Discussion Writing

For a balanced research paper discussion, read the following guidelines:

Don't Introduce Alternate Explanations Without Support:

Avoid presenting alternate explanations in the discussion without solid evidence from the results section or relevant literature. Speculation without a clear basis can weaken the effectiveness of your discussion.

Don't Overextend Into Similar Studies Without Context:

Refrain from discussing similar studies without providing proper context. While it's essential to relate your findings to existing literature, discussing similar studies should be done thoughtfully within the boundaries of your research scope.

Don't Replicate the Results Section:

Don't repeat your results over and over again during the discussion. The discussion should focus on interpretation and analysis rather than duplicating information from the results section.

Avoid Overemphasizing Conclusions:

Avoid placing too much emphasis on conclusions in the discussion section. Save comprehensive conclusions for the dedicated conclusion section of research paper . Keep the focus on interpreting your results and engaging in an effective discussion.

Don't Ignore Suggestions for Further Research:

Don't neglect to include suggestions for further research in your discussion. If you have ideas for what to do next, acknowledge them and include them in your discussion. However, avoid overloading the discussion with excessive recommendations.

Don't Disregard the Literature Review:

Avoid disregarding the research paper literature review in the discussion. Connect your findings back to the existing literature, ensuring a coherent narrative that contextualizes your results within the broader scholarly conversation.

Avoid Apologizing or Undermining:

Don't apologize or make statements that make your research seem less credible. Instead of doubting your methodology or execution, focus on addressing limitations transparently without reducing the overall impact of your study.

Don't Overstate Importance Without Support:

Refrain from overstating the importance of your findings without sufficient support. Make sure that your discussion maintains a realistic and measured tone. Always avoid grand statements that may lead readers to question the validity of your research.

Don't Neglect Transition Sentences:

Don't overlook the use of bridge sentences when reminding readers of your findings in the discussion. These sentences help smoothly transition between the results section and the interpretation, contributing to an effective and cohesive discussion.

Get Help From Some Practical Tips

Here are some tips for you to polish your discussion section to perfection.

Keep your discussion concise and directly related to your main findings
Address potential counterarguments to strengthen your discussion
Try to engage readers with thought-provoking questions
It is always a good idea to get input from peers to enhance the credibility of your discussion
Share brief personal insights or reflections on the research process
Always stick to the specific journal guidelines for the discussion section
Maintain an objective and analytical tone throughout the discussion

Discussion for a Research Paper - Examples

Looking at examples is a great idea if you want to know how to write a research paper discussion.

Example of Discussion in Research Paper PDF

Discussion for a Medical Research Paper

Example of Result and Discussion in Research Paper PDF

Example of Discussion Findings in Research

Discussion Paper Sample PDF

How to Start a Discussion in a Report

To conclude, understanding the significance of crafting a powerful research paper discussion is vital. This guide has provided valuable insights and steps for creating an impactful discussion section.

By following our steps, we’re sure that you’ll be able to write the perfect discussion section for your research paper. However, it is still easier said than done.

If you seek expert assistance or want to secure perfection in your research paper writing tasks, such as discussion, introduction, body, etc., turn to SharkPapers.com.

Professionals in our diverse pool of writers specialize in research paper writing and can skillfully handle every aspect. Our paper writing service online enhances your research paper with a precisely written discussion.

Connect with our experts today for an academic boost. Your perfectly crafted discussion section awaits a simple click away!

Frequently Asked Questions

How should one initiate the discussion section in a research paper.

To start the discussion section in a research paper, start by summarizing the key findings. Provide a concise overview of your main results, avoiding raw data repetition. This sets the stage for an in-depth analysis.

What is an example of a discussion?

An example of a discussion in the context of a research paper is when researchers analyze their study's findings, interpret the results, compare them with existing literature, and explore the implications. It involves a thoughtful conversation within the paper, similar to how individuals engage in dialogue to reconcile differing opinions.

What are the guidelines for writing a discussion in a research paper following the APA format?

When writing a discussion in a research paper following APA format, adhere to these guidelines:

Structure: Place the discussion after the introduction and before the conclusion.
Tense: Use past tense when discussing results.
Tone: Maintain an objective tone, avoiding overly speculative language.
Citations: Reference relevant literature using APA citation style.
Conciseness: Keep the discussion concise, focusing on interpretation rather than repeating results.

Jared P., a celebrated writer and writing service provider with over a decade and a half of experience, has helped countless students reach their academic goals by providing professional writing assistance. His Ph.D. in English Literature solidifies his expertise in the field and enables him to produce critical and thorough papers every time!

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The discussion section of a research paper is where the author analyzes and explains the importance of the study's results. It presents the conclusions drawn from the study, compares them to previous research, and addresses any potential limitations or weaknesses. The discussion section should also suggest areas for future research.

Everything is not that complicated if you know where to find the required information. We’ll tell you everything there is to know about writing your discussion. Our easy guide covers all important bits, including research questions and your research results. Do you know how all enumerated events are connected? Well, you will after reading this guide we’ve prepared for you!

What Is in the Discussion Section of a Research Paper

The discussion section of a research paper can be viewed as something similar to the conclusion of your paper. But not literal, of course. It’s an ultimate section where you can talk about the findings of your study. Think about these questions when writing:

Did you answer all of the promised research questions?
Did you mention why your work matters?
What are your findings, and why should anyone even care?
Does your study have a literature review?

So, answer your questions, provide proof, and don’t forget about your promises from the introduction.

How to Write a Discussion Section in 5 Steps

How to write the discussion section of a research paper is something everyone googles eventually. It's just life. But why not make everything easier? In brief, this section we’re talking about must include all following parts:

Answers for research questions
Literature review
Results of the work
Limitations of one’s study
Overall conclusion

Indeed, all those parts may confuse anyone. So by looking at our guide, you'll save yourself some hassle. P.S. All our steps are easy and explained in detail! But if you are looking for the most efficient solution, consider using professional help. Leave your “ write my research paper for me ” order at StudyCrumb and get a customized study tailored to your requirements.

Step 1. Start Strong: Discussion Section of a Research Paper

First and foremost, how to start the discussion section of a research paper? Here’s what you should definitely consider before settling down to start writing:

All essays or papers must begin strong. All readers will not wait for any writer to get to the point. We advise summarizing the paper's main findings.
Moreover, you should relate both discussion and literature review to what you have discovered. Mentioning that would be a plus too.
Make sure that an introduction or start per se is clear and concise. Word count might be needed for school. But any paper should be understandable and not too diluted.

Step 2. Answer the Questions in Your Discussion Section of a Research Paper

Writing the discussion section of a research paper also involves mentioning your questions. Remember that in your introduction, you have promised your readers to answer certain questions. Well, now it’s a perfect time to finally give the awaited answer. You need to explain all possible correlations between your findings, research questions, and literature proposed. You already had hypotheses. So were they correct, or maybe you want to propose certain corrections? Section’s main goal is to avoid open ends. It’s not a story or a fairytale with an intriguing ending. If you have several questions, you must answer them. As simple as that.

Step 3. Relate Your Results in a Discussion Section

Writing a discussion section of a research paper also requires any writer to explain their results. You will undoubtedly include an impactful literature review. However, your readers should not just try and struggle with understanding what are some specific relationships behind previous studies and your results. Your results should sound something like: “This guy in their paper discovered that apples are green. Nevertheless, I have proven via experimentation and research that apples are actually red.” Please, don’t take these results directly. It’s just an initial hypothesis. But what you should definitely remember is any practical implications of your study. Why does it matter and how can anyone use it? That’s the most crucial question.

Step 4. Describe the Limitations in Your Discussion Section

Discussion section of a research paper isn’t limitless. What does that mean? Essentially, it means that you also have to discuss any limitations of your study. Maybe you had some methodological inconsistencies. Possibly, there are no particular theories or not enough information for you to be entirely confident in one’s conclusions. You might say that an available source of literature you have studied does not focus on one’s issue. That’s why one’s main limitation is theoretical. However, keep in mind that your limitations must possess a certain degree of relevancy. You can just say that you haven’t found enough books. Your information must be truthful to research.

Step 5. Conclude Your Discussion Section With Recommendations

Your last step when you write a discussion section in a paper is its conclusion, like in any other academic work. Writer’s conclusion must be as strong as their starting point of the overall work. Check out our brief list of things to know about the conclusion in research paper :

It must present its scientific relevance and importance of your work.
It should include different implications of your research.
It should not, however, discuss anything new or things that you have not mentioned before.
Leave no open questions and carefully complete the work without them.

Discussion Section of a Research Paper Example

All the best example discussion sections of a research paper will be written according to our brief guide. Don’t forget that you need to state your findings and underline the importance of your work. An undoubtedly big part of one’s discussion will definitely be answering and explaining the research questions. In other words, you’ll already have all the knowledge you have so carefully gathered. Our last step for you is to recollect and wrap up your paper. But we’re sure you’ll succeed!

How to Write a Discussion Section: Final Thoughts

Today we have covered how to write a discussion section. That was quite a brief journey, wasn’t it? Just to remind you to focus on these things:

Importance of your study.
Summary of the information you have gathered.
Main findings and conclusions.
Answers to all research questions without an open end.
Correlation between literature review and your results.

But, wait, this guide is not the only thing we can do. Looking for how to write an abstract for a research paper for example? We have such a blog and much more on our platform.

Our academic writing service is just a click away. We are proud to say that our writers are professionals in their fields. Buy a research paper and our experts can provide prompt solutions without compromising the quality.

Discussion Section of a Research Paper: Frequently Asked Questions

1. how long should the discussion section of a research paper be.

Our discussion section of a research paper should not be longer than other sections. So try to keep it short but as informative as possible. It usually contains around 6-7 paragraphs in length. It is enough to briefly summarize all the important data and not to drag it.

2. What's the difference between the discussion and the results?

The difference between discussion and results is very simple and easy to understand. The results only report your main findings. You stated what you have found and how you have done that. In contrast, one’s discussion mentions your findings and explains how they relate to other literature, research questions, and one’s hypothesis. Therefore, it is not only a report but an efficient as well as proper explanation.

3. What's the difference between a discussion and a conclusion?

The difference between discussion and conclusion is also quite easy. Conclusion is a brief summary of all the findings and results. Still, our favorite discussion section interprets and explains your main results. It is an important but more lengthy and wordy part. Besides, it uses extra literature for references.

4. What is the purpose of the discussion section?

The primary purpose of a discussion section is to interpret and describe all your interesting findings. Therefore, you should state what you have learned, whether your hypothesis was correct and how your results can be explained using other sources. If this section is clear to readers, our congratulations as you have succeeded.

Joe Eckel is an expert on Dissertations writing. He makes sure that each student gets precious insights on composing A-grade academic writing.

How To Write The Discussion Chapter

The what, why & how explained simply (with examples).

By: Jenna Crossley (PhD Cand). Reviewed By: Dr. Eunice Rautenbach | August 2021

If you’re reading this, chances are you’ve reached the discussion chapter of your thesis or dissertation and are looking for a bit of guidance. Well, you’ve come to the right place ! In this post, we’ll unpack and demystify the typical discussion chapter in straightforward, easy to understand language, with loads of examples .

Overview: Dissertation Discussion Chapter

What (exactly) the discussion chapter is
What to include in your discussion chapter
How to write up your discussion chapter
A few tips and tricks to help you along the way

What exactly is the discussion chapter?

The discussion chapter is where you interpret and explain your results within your thesis or dissertation. This contrasts with the results chapter, where you merely present and describe the analysis findings (whether qualitative or quantitative ). In the discussion chapter, you elaborate on and evaluate your research findings, and discuss the significance and implications of your results.

In this chapter, you’ll situate your research findings in terms of your research questions or hypotheses and tie them back to previous studies and literature (which you would have covered in your literature review chapter). You’ll also have a look at how relevant and/or significant your findings are to your field of research, and you’ll argue for the conclusions that you draw from your analysis. Simply put, the discussion chapter is there for you to interact with and explain your research findings in a thorough and coherent manner.

What should I include in the discussion chapter?

First things first: in some studies, the results and discussion chapter are combined into one chapter . This depends on the type of study you conducted (i.e., the nature of the study and methodology adopted), as well as the standards set by the university. So, check in with your university regarding their norms and expectations before getting started. In this post, we’ll treat the two chapters as separate, as this is most common.

Basically, your discussion chapter should analyse , explore the meaning and identify the importance of the data you presented in your results chapter. In the discussion chapter, you’ll give your results some form of meaning by evaluating and interpreting them. This will help answer your research questions, achieve your research aims and support your overall conclusion (s). Therefore, you discussion chapter should focus on findings that are directly connected to your research aims and questions. Don’t waste precious time and word count on findings that are not central to the purpose of your research project.

As this chapter is a reflection of your results chapter, it’s vital that you don’t report any new findings . In other words, you can’t present claims here if you didn’t present the relevant data in the results chapter first. So, make sure that for every discussion point you raise in this chapter, you’ve covered the respective data analysis in the results chapter. If you haven’t, you’ll need to go back and adjust your results chapter accordingly.

If you’re struggling to get started, try writing down a bullet point list everything you found in your results chapter. From this, you can make a list of everything you need to cover in your discussion chapter. Also, make sure you revisit your research questions or hypotheses and incorporate the relevant discussion to address these. This will also help you to see how you can structure your chapter logically.

Need a helping hand?

How to write the discussion chapter

Now that you’ve got a clear idea of what the discussion chapter is and what it needs to include, let’s look at how you can go about structuring this critically important chapter. Broadly speaking, there are six core components that need to be included, and these can be treated as steps in the chapter writing process.

Step 1: Restate your research problem and research questions

The first step in writing up your discussion chapter is to remind your reader of your research problem , as well as your research aim(s) and research questions . If you have hypotheses, you can also briefly mention these. This “reminder” is very important because, after reading dozens of pages, the reader may have forgotten the original point of your research or been swayed in another direction. It’s also likely that some readers skip straight to your discussion chapter from the introduction chapter , so make sure that your research aims and research questions are clear.

Step 2: Summarise your key findings

Next, you’ll want to summarise your key findings from your results chapter. This may look different for qualitative and quantitative research , where qualitative research may report on themes and relationships, whereas quantitative research may touch on correlations and causal relationships. Regardless of the methodology, in this section you need to highlight the overall key findings in relation to your research questions.

Typically, this section only requires one or two paragraphs , depending on how many research questions you have. Aim to be concise here, as you will unpack these findings in more detail later in the chapter. For now, a few lines that directly address your research questions are all that you need.

Some examples of the kind of language you’d use here include:

The data suggest that…
The data support/oppose the theory that…
The analysis identifies…

These are purely examples. What you present here will be completely dependent on your original research questions, so make sure that you are led by them .

Step 3: Interpret your results

Once you’ve restated your research problem and research question(s) and briefly presented your key findings, you can unpack your findings by interpreting your results. Remember: only include what you reported in your results section – don’t introduce new information.

From a structural perspective, it can be a wise approach to follow a similar structure in this chapter as you did in your results chapter. This would help improve readability and make it easier for your reader to follow your arguments. For example, if you structured you results discussion by qualitative themes, it may make sense to do the same here.

Alternatively, you may structure this chapter by research questions, or based on an overarching theoretical framework that your study revolved around. Every study is different, so you’ll need to assess what structure works best for you.

When interpreting your results, you’ll want to assess how your findings compare to those of the existing research (from your literature review chapter). Even if your findings contrast with the existing research, you need to include these in your discussion. In fact, those contrasts are often the most interesting findings . In this case, you’d want to think about why you didn’t find what you were expecting in your data and what the significance of this contrast is.

Here are a few questions to help guide your discussion:

How do your results relate with those of previous studies ?
If you get results that differ from those of previous studies, why may this be the case?
What do your results contribute to your field of research?
What other explanations could there be for your findings?

When interpreting your findings, be careful not to draw conclusions that aren’t substantiated . Every claim you make needs to be backed up with evidence or findings from the data (and that data needs to be presented in the previous chapter – results). This can look different for different studies; qualitative data may require quotes as evidence, whereas quantitative data would use statistical methods and tests. Whatever the case, every claim you make needs to be strongly backed up.

Step 4: Acknowledge the limitations of your study

The fourth step in writing up your discussion chapter is to acknowledge the limitations of the study. These limitations can cover any part of your study , from the scope or theoretical basis to the analysis method(s) or sample. For example, you may find that you collected data from a very small sample with unique characteristics, which would mean that you are unable to generalise your results to the broader population.

For some students, discussing the limitations of their work can feel a little bit self-defeating . This is a misconception, as a core indicator of high-quality research is its ability to accurately identify its weaknesses. In other words, accurately stating the limitations of your work is a strength, not a weakness . All that said, be careful not to undermine your own research. Tell the reader what limitations exist and what improvements could be made, but also remind them of the value of your study despite its limitations.

Step 5: Make recommendations for implementation and future research

Now that you’ve unpacked your findings and acknowledge the limitations thereof, the next thing you’ll need to do is reflect on your study in terms of two factors:

The practical application of your findings
Suggestions for future research

The first thing to discuss is how your findings can be used in the real world – in other words, what contribution can they make to the field or industry? Where are these contributions applicable, how and why? For example, if your research is on communication in health settings, in what ways can your findings be applied to the context of a hospital or medical clinic? Make sure that you spell this out for your reader in practical terms, but also be realistic and make sure that any applications are feasible.

The next discussion point is the opportunity for future research . In other words, how can other studies build on what you’ve found and also improve the findings by overcoming some of the limitations in your study (which you discussed a little earlier). In doing this, you’ll want to investigate whether your results fit in with findings of previous research, and if not, why this may be the case. For example, are there any factors that you didn’t consider in your study? What future research can be done to remedy this? When you write up your suggestions, make sure that you don’t just say that more research is needed on the topic, also comment on how the research can build on your study.

Step 6: Provide a concluding summary

Finally, you’ve reached your final stretch. In this section, you’ll want to provide a brief recap of the key findings – in other words, the findings that directly address your research questions . Basically, your conclusion should tell the reader what your study has found, and what they need to take away from reading your report.

When writing up your concluding summary, bear in mind that some readers may skip straight to this section from the beginning of the chapter. So, make sure that this section flows well from and has a strong connection to the opening section of the chapter.

Tips and tricks for an A-grade discussion chapter

Now that you know what the discussion chapter is , what to include and exclude , and how to structure it , here are some tips and suggestions to help you craft a quality discussion chapter.

When you write up your discussion chapter, make sure that you keep it consistent with your introduction chapter , as some readers will skip from the introduction chapter directly to the discussion chapter. Your discussion should use the same tense as your introduction, and it should also make use of the same key terms.
Don’t make assumptions about your readers. As a writer, you have hands-on experience with the data and so it can be easy to present it in an over-simplified manner. Make sure that you spell out your findings and interpretations for the intelligent layman.
Have a look at other theses and dissertations from your institution, especially the discussion sections. This will help you to understand the standards and conventions of your university, and you’ll also get a good idea of how others have structured their discussion chapters. You can also check out our chapter template .
Avoid using absolute terms such as “These results prove that…”, rather make use of terms such as “suggest” or “indicate”, where you could say, “These results suggest that…” or “These results indicate…”. It is highly unlikely that a dissertation or thesis will scientifically prove something (due to a variety of resource constraints), so be humble in your language.
Use well-structured and consistently formatted headings to ensure that your reader can easily navigate between sections, and so that your chapter flows logically and coherently.

If you have any questions or thoughts regarding this post, feel free to leave a comment below. Also, if you’re looking for one-on-one help with your discussion chapter (or thesis in general), consider booking a free consultation with one of our highly experienced Grad Coaches to discuss how we can help you.

Psst... there’s more!

This post was based on one of our popular Research Bootcamps . If you're working on a research project, you'll definitely want to check this out ...

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How to write the conclusion chapter of a dissertation

36 Comments

Thank you this is helpful!

This is very helpful to me… Thanks a lot for sharing this with us 😊

This has been very helpful indeed. Thank you.

This is actually really helpful, I just stumbled upon it. Very happy that I found it, thank you.

Me too! I was kinda lost on how to approach my discussion chapter. How helpful! Thanks a lot!

This is really good and explicit. Thanks

Thank you, this blog has been such a help.

Thank you. This is very helpful.

Dear sir/madame

Thanks a lot for this helpful blog. Really, it supported me in writing my discussion chapter while I was totally unaware about its structure and method of writing.

With regards

Syed Firoz Ahmad PhD, Research Scholar

I agree so much. This blog was god sent. It assisted me so much while I was totally clueless about the context and the know-how. Now I am fully aware of what I am to do and how I am to do it.

Thanks! This is helpful!

thanks alot for this informative website

Dear Sir/Madam,

Truly, your article was much benefited when i structured my discussion chapter.

Thank you very much!!!

This is helpful for me in writing my research discussion component. I have to copy this text on Microsoft word cause of my weakness that I cannot be able to read the text on screen a long time. So many thanks for this articles.

This was helpful

Thanks Jenna, well explained.

Thank you! This is super helpful.

Thanks very much. I have appreciated the six steps on writing the Discussion chapter which are (i) Restating the research problem and questions (ii) Summarising the key findings (iii) Interpreting the results linked to relating to previous results in positive and negative ways; explaining whay different or same and contribution to field of research and expalnation of findings (iv) Acknowledgeing limitations (v) Recommendations for implementation and future resaerch and finally (vi) Providing a conscluding summary

My two questions are: 1. On step 1 and 2 can it be the overall or you restate and sumamrise on each findings based on the reaerch question? 2. On 4 and 5 do you do the acknowlledgement , recommendations on each research finding or overall. This is not clear from your expalanattion.

Please respond.

This post is very useful. I’m wondering whether practical implications must be introduced in the Discussion section or in the Conclusion section?

Sigh, I never knew a 20 min video could have literally save my life like this. I found this at the right time!!!! Everything I need to know in one video thanks a mil ! OMGG and that 6 step!!!!!! was the cherry on top the cake!!!!!!!!!

Thanks alot.., I have gained much

This piece is very helpful on how to go about my discussion section. I can always recommend GradCoach research guides for colleagues.

Many thanks for this resource. It has been very helpful to me. I was finding it hard to even write the first sentence. Much appreciated.

Thanks so much. Very helpful to know what is included in the discussion section

this was a very helpful and useful information

This is very helpful. Very very helpful. Thanks for sharing this online!

it is very helpfull article, and i will recommend it to my fellow students. Thank you.

Superlative! More grease to your elbows.

Powerful, thank you for sharing.

Wow! Just wow! God bless the day I stumbled upon you guys’ YouTube videos! It’s been truly life changing and anxiety about my report that is due in less than a month has subsided significantly!

Simplified explanation. Well done.

The presentation is enlightening. Thank you very much.

Thanks for the support and guidance

This has been a great help to me and thank you do much

I second that “it is highly unlikely that a dissertation or thesis will scientifically prove something”; although, could you enlighten us on that comment and elaborate more please?

Sure, no problem.

Scientific proof is generally considered a very strong assertion that something is definitively and universally true. In most scientific disciplines, especially within the realms of natural and social sciences, absolute proof is very rare. Instead, researchers aim to provide evidence that supports or rejects hypotheses. This evidence increases or decreases the likelihood that a particular theory is correct, but it rarely proves something in the absolute sense.

Dissertations and theses, as substantial as they are, typically focus on exploring a specific question or problem within a larger field of study. They contribute to a broader conversation and body of knowledge. The aim is often to provide detailed insight, extend understanding, and suggest directions for further research rather than to offer definitive proof. These academic works are part of a cumulative process of knowledge building where each piece of research connects with others to gradually enhance our understanding of complex phenomena.

Furthermore, the rigorous nature of scientific inquiry involves continuous testing, validation, and potential refutation of ideas. What might be considered a “proof” at one point can later be challenged by new evidence or alternative interpretations. Therefore, the language of “proof” is cautiously used in academic circles to maintain scientific integrity and humility.

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General Research Paper Guidelines: Discussion

Discussion section.

The overall purpose of a research paper’s discussion section is to evaluate and interpret results, while explaining both the implications and limitations of your findings. Per APA (2020) guidelines, this section requires you to “examine, interpret, and qualify the results and draw inferences and conclusions from them” (p. 89). Discussion sections also require you to detail any new insights, think through areas for future research, highlight the work that still needs to be done to further your topic, and provide a clear conclusion to your research paper. In a good discussion section, you should do the following:

Clearly connect the discussion of your results to your introduction, including your central argument, thesis, or problem statement.
Provide readers with a critical thinking through of your results, answering the “so what?” question about each of your findings. In other words, why is this finding important?
Detail how your research findings might address critical gaps or problems in your field
Compare your results to similar studies’ findings
Provide the possibility of alternative interpretations, as your goal as a researcher is to “discover” and “examine” and not to “prove” or “disprove.” Instead of trying to fit your results into your hypothesis, critically engage with alternative interpretations to your results.

For more specific details on your Discussion section, be sure to review Sections 3.8 (pp. 89-90) and 3.16 (pp. 103-104) of your 7 th edition APA manual

*Box content adapted from:

University of Southern California (n.d.). Organizing your social sciences research paper: 8 the discussion . https://libguides.usc.edu/writingguide/discussion

Limitations

Limitations of generalizability or utility of findings, often over which the researcher has no control, should be detailed in your Discussion section. Including limitations for your reader allows you to demonstrate you have thought critically about your given topic, understood relevant literature addressing your topic, and chosen the methodology most appropriate for your research. It also allows you an opportunity to suggest avenues for future research on your topic. An effective limitations section will include the following:

Detail (a) sources of potential bias, (b) possible imprecision of measures, (c) other limitations or weaknesses of the study, including any methodological or researcher limitations.
Sample size: In quantitative research, if a sample size is too small, it is more difficult to generalize results.
Lack of available/reliable data : In some cases, data might not be available or reliable, which will ultimately affect the overall scope of your research. Use this as an opportunity to explain areas for future study.
Lack of prior research on your study topic: In some cases, you might find that there is very little or no similar research on your study topic, which hinders the credibility and scope of your own research. If this is the case, use this limitation as an opportunity to call for future research. However, make sure you have done a thorough search of the available literature before making this claim.
Flaws in measurement of data: Hindsight is 20/20, and you might realize after you have completed your research that the data tool you used actually limited the scope or results of your study in some way. Again, acknowledge the weakness and use it as an opportunity to highlight areas for future study.
Limits of self-reported data: In your research, you are assuming that any participants will be honest and forthcoming with responses or information they provide to you. Simply acknowledging this assumption as a possible limitation is important in your research.
Access: Most research requires that you have access to people, documents, organizations, etc.. However, for various reasons, access is sometimes limited or denied altogether. If this is the case, you will want to acknowledge access as a limitation to your research.
Time: Choosing a research focus that is narrow enough in scope to finish in a given time period is important. If such limitations of time prevent you from certain forms of research, access, or study designs, acknowledging this time restraint is important. Acknowledging such limitations is important, as they can point other researchers to areas that require future study.
Potential Bias: All researchers have some biases, so when reading and revising your draft, pay special attention to the possibilities for bias in your own work. Such bias could be in the form you organized people, places, participants, or events. They might also exist in the method you selected or the interpretation of your results. Acknowledging such bias is an important part of the research process.
Language Fluency: On occasion, researchers or research participants might have language fluency issues, which could potentially hinder results or how effectively you interpret results. If this is an issue in your research, make sure to acknowledge it in your limitations section.

University of Southern California (n.d.). Organizing your social sciences research paper: Limitations of the study . https://libguides.usc.edu/writingguide/limitations

In many research papers, the conclusion, like the limitations section, is folded into the larger discussion section. If you are unsure whether to include the conclusion as part of your discussion or as a separate section, be sure to defer to the assignment instructions or ask your instructor.

The conclusion is important, as it is specifically designed to highlight your research’s larger importance outside of the specific results of your study. Your conclusion section allows you to reiterate the main findings of your study, highlight their importance, and point out areas for future research. Based on the scope of your paper, your conclusion could be anywhere from one to three paragraphs long. An effective conclusion section should include the following:

Describe the possibilities for continued research on your topic, including what might be improved, adapted, or added to ensure useful and informed future research.
Provide a detailed account of the importance of your findings
Reiterate why your problem is important, detail how your interpretation of results impacts the subfield of study, and what larger issues both within and outside of your field might be affected from such results

University of Southern California (n.d.). Organizing your social sciences research paper: 9. the conclusion . https://libguides.usc.edu/writingguide/conclusion

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How to Start a Discussion Section in Research? [with Examples]

The examples below are from 72,017 full-text PubMed research papers that I analyzed in order to explore common ways to start writing the Discussion section.

Research papers included in this analysis were selected at random from those uploaded to PubMed Central between the years 2016 and 2021. Note that I used the BioC API to download the data (see the References section below).

Examples of how to start writing the Discussion section

In the Discussion section, you should explain the meaning of your results, their importance, and implications. [for more information, see: How to Write & Publish a Research Paper: Step-by-Step Guide ]

The Discussion section can:

1. Start by restating the study objective

“ The purpose of this study was to investigate the relationship between muscle synergies and motion primitives of the upper limb motions.” Taken from the Discussion section of this article on PubMed

“ The main objective of this study was to identify trajectories of autonomy.” Taken from the Discussion section of this article on PubMed

“ In the present study, we investigated the whole brain regional homogeneity in patients with melancholic MDD and non-melancholic MDD at rest . “ Taken from the Discussion section of this article on PubMed

2. Start by mentioning the main finding

“ We found that autocracy and democracy have acted as peaks in an evolutionary landscape of possible modes of institutional arrangements.” Taken from the Discussion section of this article on PubMed

“ In this study, we demonstrated that the neural mechanisms of rhythmic movements and skilled movements are similar.” Taken from the Discussion section of this article on PubMed

“ The results of this study show that older adults are a diverse group concerning their activities on the Internet.” Taken from the Discussion section of this article on PubMed

3. Start by pointing out the strength of the study

“ To our knowledge, this investigation is by far the largest epidemiological study employing real-time PCR to study periodontal pathogens in subgingival plaque.” Taken from the Discussion section of this article on PubMed

“ This is the first human subject research using the endoscopic hemoglobin oxygen saturation imaging technology for patients with aero-digestive tract cancers or adenomas.” Taken from the Discussion section of this article on PubMed

“ In this work, we introduced a new real-time flow imaging method and systematically demonstrated its effectiveness with both flow phantom experiments and in vivo experiments.” Taken from the Discussion section of this article on PubMed

Most used words at the start of the Discussion

Here are the top 10 phrases used to start a discussion section in our dataset:

Comeau DC, Wei CH, Islamaj Doğan R, and Lu Z. PMC text mining subset in BioC: about 3 million full text articles and growing, Bioinformatics , btz070, 2019.

How to Write a Discussion Section of a Research Paper

The purpose of the discussion section

Structure and Writing Style

Step-by-step writing guide
Tips for writing a discussion
Discussion section example

How to Write a Discussion Section of a Research Paper

The Purpose of the Discussion Section in a Research Paper

A summary of your work. Don’t rewrite the results section. Briefly summarize what you’ve explored, and remind readers about that.
Interpretation of your result. The following important part of the discussion section is to talk about what your results mean. What are the results of your research?
Your recommendations. Tell readers about what suggestions you give in connection with the results obtained. Perhaps locally to solve the problem or in general some preventive measures. But be careful! Do not give any speculative recommendations that are not supported by your research. Also, do not focus on what did not work out or where mistakes were made.
Be concise, and don’t repeat yourself. Express your thoughts clearly and consistently so the reader immediately understands what you are discussing. Do not repeat sections of your work or retell the same idea several times in different words.
Avoid using jargon or complex, obscure words. Everyone who reads your work should understand what you want to say without a dictionary or additional books.
Be bold and cite other authors and studies to support your conclusions and thoughts.
If your discussion section is too long, you can use subheadings to group ideas together so you don’t forget anything while writing.
Comment on your results , even if they were unexpected or random. Feel free to go into details.
You can add hypotheses or assumptions that will be explored in your following works. This way, you show the depth of the results and their significance.
You can start writing a discussion in scientific paper from general problems and perspectives on solving them to specific aspects. You can also offer some options for practical solutions to issues.
Remember to describe general patterns, principles, and relationships in the problem under study.
If you find some unexpected result, describe how you came to it and how it will affect the question.
At the end of the discussion section, you should state why the results are significant and how they affect broader research topics.

6 Steps to Write a Discussion in Research Paper

Step 1. write down the conclusions you want to make in the discussion section, step 2. start the discussion with the problem and results, step 3: formulate your interpretations of the research paper discussion, step 4. describe the consequences in the discussion section, step 5. talk about limitations in your discussion part, step 6. summarize and share recommendations in the discussion section, tips for writing a discussion section.

Once you have established the context, presenting a well-supported argument with relevant evidence and examples is essential. It means you should analyze the data collected during your research and use it to support your claims. Provide specific examples and use straightforward language to explain your findings.
Ensuring that your discussion is easy to follow and understand is crucial. Avoid using technical jargon, and break up complex ideas into smaller, more manageable chunks. It will help your readers stay engaged and easily follow your argument.
Visual aids such as graphs, charts, or tables can also be beneficial, allowing you to present data clearly and concisely. These visual aids can help to illustrate your points and make your argument more compelling.
Finally, engaging with your audience and creating a sense of dialogue throughout your writing is essential. It can be achieved by addressing counterarguments and inviting feedback and discussion from your readers. Doing so can create a more engaging and thought-provoking discussion section.

Example of Discussion in Research Paper

In the discussion section, we will delve deeper into the findings of our study and explore their implications. Our research showed a strong correlation between regular exercise and improved mental health. This finding is consistent with previous studies in the field and reinforces the importance of physical activity for overall well-being.

We also found that social support plays a significant role in promoting exercise adherence and mental health outcomes. Participants who reported having supportive friends and family members were more likely to exercise regularly and experience positive mental health outcomes.

However, our study had limitations that should be acknowledged. Firstly, our sample size was small, and we only recruited participants from one location. Future studies should aim to recruit a more extensive and more diverse sample. Secondly, our study relied on self-reported measures of exercise and mental health, which can be subject to bias.

Overall, our findings suggest that promoting regular exercise and social support can effectively improve mental health outcomes. Further research is needed to explore the mechanisms underlying these relationships and to identify specific interventions that can be implemented to promote exercise and social support.

Writing a Research Paper
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Research Paper Problem Statement
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Hypothesis for a Research Paper
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Research Paper Prospectus
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Organizing Academic Research Papers: 8. The Discussion

Purpose of Guide
Design Flaws to Avoid
Glossary of Research Terms
Narrowing a Topic Idea
Broadening a Topic Idea
Extending the Timeliness of a Topic Idea
Academic Writing Style
Choosing a Title
Making an Outline
Paragraph Development
Executive Summary
Background Information
The Research Problem/Question
Theoretical Framework
Citation Tracking
Content Alert Services
Evaluating Sources
Primary Sources
Secondary Sources
Tertiary Sources
What Is Scholarly vs. Popular?
Qualitative Methods
Quantitative Methods
Using Non-Textual Elements
Limitations of the Study
Common Grammar Mistakes
Avoiding Plagiarism
Footnotes or Endnotes?
Further Readings
Annotated Bibliography
Dealing with Nervousness
Using Visual Aids
Grading Someone Else's Paper
How to Manage Group Projects
Multiple Book Review Essay
Reviewing Collected Essays
About Informed Consent
Writing Field Notes
Writing a Policy Memo
Writing a Research Proposal
Acknowledgements

The purpose of the discussion is to interpret and describe the significance of your findings in light of what was already known about the research problem being investigated, and to explain any new understanding or fresh insights about the problem after you've taken the findings into consideration. The discussion will always connect to the introduction by way of the research questions or hypotheses you posed and the literature you reviewed, but it does not simply repeat or rearrange the introduction; the discussion should always explain how your study has moved the reader's understanding of the research problem forward from where you left them at the end of the introduction.

Importance of a Good Discussion

This section is often considered the most important part of a research paper because it most effectively demonstrates your ability as a researcher to think critically about an issue, to develop creative solutions to problems based on the findings, and to formulate a deeper, more profound understanding of the research problem you are studying.

The discussion section is where you explore the underlying meaning of your research , its possible implications in other areas of study, and the possible improvements that can be made in order to further develop the concerns of your research.

This is the section where you need to present the importance of your study and how it may be able to contribute to and/or fill existing gaps in the field. If appropriate, the discussion section is also where you state how the findings from your study revealed new gaps in the literature that had not been previously exposed or adequately described.

This part of the paper is not strictly governed by objective reporting of information but, rather, it is where you can engage in creative thinking about issues through evidence-based interpretation of findings. This is where you infuse your results with meaning.

Kretchmer, Paul. Fourteen Steps to Writing to Writing an Effective Discussion Section . San Francisco Edit, 2003-2008.

Structure and Writing Style

I. General Rules

These are the general rules you should adopt when composing your discussion of the results :

Do not be verbose or repetitive.
Be concise and make your points clearly.
Avoid using jargon.
Follow a logical stream of thought.
Use the present verb tense, especially for established facts; however, refer to specific works and references in the past tense.
If needed, use subheadings to help organize your presentation or to group your interpretations into themes.

II. The Content

The content of the discussion section of your paper most often includes :

Explanation of results : comment on whether or not the results were expected and present explanations for the results; go into greater depth when explaining findings that were unexpected or especially profound. If appropriate, note any unusual or unanticipated patterns or trends that emerged from your results and explain their meaning.
References to previous research : compare your results with the findings from other studies, or use the studies to support a claim. This can include re-visiting key sources already cited in your literature review section, or, save them to cite later in the discussion section if they are more important to compare with your results than being part of the general research you cited to provide context and background information.
Deduction : a claim for how the results can be applied more generally. For example, describing lessons learned, proposing recommendations that can help improve a situation, or recommending best practices.
Hypothesis : a more general claim or possible conclusion arising from the results [which may be proved or disproved in subsequent research].

III. Organization and Structure

Keep the following sequential points in mind as you organize and write the discussion section of your paper:

Think of your discussion as an inverted pyramid. Organize the discussion from the general to the specific, linking your findings to the literature, then to theory, then to practice [if appropriate].
Use the same key terms, mode of narration, and verb tense [present] that you used when when describing the research problem in the introduction.
Begin by briefly re-stating the research problem you were investigating and answer all of the research questions underpinning the problem that you posed in the introduction.
Describe the patterns, principles, and relationships shown by each major findings and place them in proper perspective. The sequencing of providing this information is important; first state the answer, then the relevant results, then cite the work of others. If appropriate, refer the reader to a figure or table to help enhance the interpretation of the data. The order of interpreting each major finding should be in the same order as they were described in your results section.
A good discussion section includes analysis of any unexpected findings. This paragraph should begin with a description of the unexpected finding, followed by a brief interpretation as to why you believe it appeared and, if necessary, its possible significance in relation to the overall study. If more than one unexpected finding emerged during the study, describe each them in the order they appeared as you gathered the data.
Before concluding the discussion, identify potential limitations and weaknesses. Comment on their relative importance in relation to your overall interpretation of the results and, if necessary, note how they may affect the validity of the findings. Avoid using an apologetic tone; however, be honest and self-critical.
The discussion section should end with a concise summary of the principal implications of the findings regardless of statistical significance. Give a brief explanation about why you believe the findings and conclusions of your study are important and how they support broader knowledge or understanding of the research problem. This can be followed by any recommendations for further research. However, do not offer recommendations which could have been easily addressed within the study. This demonstrates to the reader you have inadequately examined and interpreted the data.

IV. Overall Objectives

The objectives of your discussion section should include the following: I. Reiterate the Research Problem/State the Major Findings

Briefly reiterate for your readers the research problem or problems you are investigating and the methods you used to investigate them, then move quickly to describe the major findings of the study. You should write a direct, declarative, and succinct proclamation of the study results.

II. Explain the Meaning of the Findings and Why They are Important

No one has thought as long and hard about your study as you have. Systematically explain the meaning of the findings and why you believe they are important. After reading the discussion section, you want the reader to think about the results [“why hadn’t I thought of that?”]. You don’t want to force the reader to go through the paper multiple times to figure out what it all means. Begin this part of the section by repeating what you consider to be your most important finding first.

III. Relate the Findings to Similar Studies

No study is so novel or possesses such a restricted focus that it has absolutely no relation to other previously published research. The discussion section should relate your study findings to those of other studies, particularly if questions raised by previous studies served as the motivation for your study, the findings of other studies support your findings [which strengthens the importance of your study results], and/or they point out how your study differs from other similar studies. IV. Consider Alternative Explanations of the Findings

It is important to remember that the purpose of research is to discover and not to prove . When writing the discussion section, you should carefully consider all possible explanations for the study results, rather than just those that fit your prior assumptions or biases.

V. Acknowledge the Study’s Limitations

It is far better for you to identify and acknowledge your study’s limitations than to have them pointed out by your professor! Describe the generalizability of your results to other situations, if applicable to the method chosen, then describe in detail problems you encountered in the method(s) you used to gather information. Note any unanswered questions or issues your study did not address, and.... VI. Make Suggestions for Further Research

Although your study may offer important insights about the research problem, other questions related to the problem likely remain unanswered. Moreover, some unanswered questions may have become more focused because of your study. You should make suggestions for further research in the discussion section.

NOTE: Besides the literature review section, the preponderance of references to sources in your research paper are usually found in the discussion section . A few historical references may be helpful for perspective but most of the references should be relatively recent and included to aid in the interpretation of your results and/or linked to similar studies. If a study that you cited disagrees with your findings, don't ignore it--clearly explain why the study's findings differ from yours.

V. Problems to Avoid

Do not waste entire sentences restating your results . Should you need to remind the reader of the finding to be discussed, use "bridge sentences" that relate the result to the interpretation. An example would be: “The lack of available housing to single women with children in rural areas of Texas suggests that...[then move to the interpretation of this finding].”
Recommendations for further research can be included in either the discussion or conclusion of your paper but do not repeat your recommendations in the both sections.
Do not introduce new results in the discussion. Be wary of mistaking the reiteration of a specific finding for an interpretation.
Use of the first person is acceptable, but too much use of the first person may actually distract the reader from the main points.

Analyzing vs. Summarizing. Department of English Writing Guide. George Mason University; Discussion . The Structure, Format, Content, and Style of a Journal-Style Scientific Paper. Department of Biology. Bates College; Hess, Dean R. How to Write an Effective Discussion. Respiratory Care 49 (October 2004); Kretchmer, Paul. Fourteen Steps to Writing to Writing an Effective Discussion Section . San Francisco Edit, 2003-2008; The Lab Report . University College Writing Centre. University of Toronto; Summary: Using it Wisely . The Writing Center. University of North Carolina; Schafer, Mickey S. Writing the Discussion . Writing in Psychology course syllabus. University of Florida; Yellin, Linda L. A Sociology Writer's Guide. Boston, MA: Allyn and Bacon, 2009.

Writing Tip

Don’t Overinterpret the Results!

Interpretation is a subjective exercise. Therefore, be careful that you do not read more into the findings than can be supported by the evidence you've gathered. Remember that the data are the data: nothing more, nothing less.

Another Writing Tip

Don't Write Two Results Sections!

Azar, Beth. Discussing Your Findings. American Psychological Association gradPSYCH Magazine (January 2006)

Yet Another Writing Tip

Avoid Unwarranted Speculation!

The discussion section should remain focused on the findings of your study. For example, if you studied the impact of foreign aid on increasing levels of education among the poor in Bangladesh, it's generally not appropriate to speculate about how your findings might apply to populations in other countries without drawing from existing studies to support your claim. If you feel compelled to speculate, be certain that you clearly identify your comments as speculation or as a suggestion for where further research is needed. Sometimes your professor will encourage you to expand the discussion in this way, while others don’t care what your opinion is beyond your efforts to interpret the data.

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Next: Limitations of the Study >>
Last Updated: Jul 18, 2023 11:58 AM
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Research Paper Guide

Research Paper Discussion Section

How To Write A Discussion For A Research Paper | Examples & Tips

What Exactly is a Discussion Section in the Research Paper?

In a research paper, the discussion section is where you explain what your results really mean. It's like answering the questions, "So what?" and "What's the big picture?"

The discussion section is your chance to help your readers understand why your findings are important and how they fit into the larger context. It's more than just summarizing; it's about making your research understandable and meaningful to others.

Importance of the Discussion Section

The discussion section isn't just a formality; it's the heart of your research paper. This is where your findings transform from data into knowledge.

Let's break down why it's so crucial:

Interpretation of Results : The discussion is where you get to tell readers what your results really mean. You go into the details, helping them understand the story behind the numbers or findings.
Connecting the Dots : You connect different parts of your research, showing how they relate. This helps your readers see the bigger picture.
Relevance to the Big Picture : You get to highlight why your research matters. How does it contribute to the broader understanding of the topic? This is your time to make your research significant.
Addressing Limitations : In the discussion, you can acknowledge any limitations in your study and discuss how they might impact your results.
Suggestions for Further Research : The discussion is where you suggest areas for future exploration. It's like passing the baton to the next researcher, indicating where more work could be done.

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How to Write the Discussion Section of a Research Paper?

The Discussion section in a research paper plays a vital role in interpreting findings and formulating a conclusion . Given below are the main components of the discussion section:

Quick Summary: A brief recap of your main findings.
Interpretation: Significance and meaning of your results in relation to your research question.
Literature Review : Connecting your findings with previous research or similar studies.
Limitations: Discussing any study limitations, addressing potential concerns.
Implications: Broader implications of your findings, considering practical and theoretical aspects.
Alternative Explanations: Evaluating alternative interpretations, demonstrating a comprehensive analysis.
Connecting to Hypotheses : Summarizing how your result section aligns or diverges from your initial hypotheses.

Now let’s explore the steps to write an effective discussion section that will effectively communicate the significance of your research:

Step 1: Get Started with a Quick Summary

Start by quickly telling your readers the main things you found in your research. Don't explain them in detail just yet; just give a simple overview.

This helps your readers get the big picture before diving into the details.

Step 2: Interpret Your Results

In the next step, talk about what your findings really mean. Share why the information you gathered is important. Connect each result to the questions you were trying to answer and the goals you set for your research.

Step 3: Relate to Existing Literature

In this step, link up your discoveries with what other researchers have already figured out.

Share if your results are similar to or different from what's been found before. This helps give more background to your study and shows you know what other scientists have been up to.

Step 4: Address Limitations Honestly

Every study has its limitations. Acknowledge them openly in your discussion. This not only shows transparency but also helps readers interpret your results more accurately.

Step 5: Discuss the Implications

Explore the implications of your findings. How do they contribute to the field? What real-world applications or changes might they suggest?

Dig into why your discoveries are important. How do they help the subject you studied?

This step is like looking at the bigger picture and asking, "So, what can we do with this information?"

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Step 6: Consider Alternative Explanations

After discussing the implications, challenge yourself by exploring alternative explanations for your results.

Discuss different perspectives and show that you've considered multiple angles.

Step 7: Connect to Your Hypotheses or Research Questions

For the last step, revisit your initial hypotheses or research questions. Explain whether your results support what you thought might happen or if they surprised you.

Examples of Good Discussion for a Research Paper

Learning from well-crafted discussions can significantly enhance your own writing. Given below are some examples to help you understand how to write your own.

Discussion for a Research Paper Example Pdf

Discussion for a Medical Research Paper

Discussion Section for a Qualitative Research Paper

Mistakes to Avoid in Your Research Paper's Discussion

Writing the discussion section of your research paper can be tricky. To make sure you're on the right track, be mindful of these common mistakes:

Overstating or Overinterpreting Results

Avoid making your findings sound more groundbreaking than they are. Stick to what your data actually shows, and don't exaggerate.

Neglecting Alternative Explanations

Failing to consider other possible explanations for your results can weaken your discussion. Always explore alternative perspectives to present a well-rounded view.

Ignoring Limitations

Don't sweep limitations under the rug. Acknowledge them openly and discuss how they might affect the validity or generalizability of your results.

Being Overly Technical or Jargon-laden

Remember that your audience may not be experts in your specific field. Avoid using overly technical language or excessive jargon that could alienate your readers.

Disregarding the 'So What' Factor

Always explain the significance of your findings. Don't leave your readers wondering why your research matters or how it contributes to the broader understanding of the subject.

Rushing the Conclusion

The conclusion section of your discussion is critical. Don't rush it. Summarize the key points and leave your readers with a strong understanding of the significance of your research.

So, there you have it —writing a discussion and conclusion section isn't easy, but avoiding some common mistakes can make it much smoother.

Remember to keep it real with your results, think about what else could explain things, and don't forget about any limits in your study.

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How To Write A Research Paper

Research Paper Discussion Section

How to Write a Discussion For a Research Paper | Objectives, Steps & Examples

10 min read

Published on: Mar 6, 2024

Last updated on: Mar 5, 2024

What is the Discussion Section in Research?

The discussion section is where the author interprets the results, contextualizes findings within the existing literature and engages in thoughtful analysis.

According to the American Psychological Association (APA), the discussion is the space for reflection, providing a bridge between the results and the overall conclusion.

The discussion section typically follows the results section but precedes the conclusion.

People may sometimes confuse discussions and conclusions sections. While the conclusion summarizes key points, the discussion section interprets and analyzes the results in detail. The discussion goes beyond summarization, offering a deeper understanding of the study's implications and contributing to the scholarly conversation.

Elements of Discussion Section

The discussion section in a research paper comprises the following key elements:

Summary : What are the main findings in a nutshell?
Interpretations : How do you explain your results?
Implications : Why are your findings important in the broader context?
Limitations : What are the constraints in your methodology or data?
Recommendations : What future studies or improvements arise from your outcomes?

Main Objectives of Discussion Section

The primary objectives of the discussion section include:

To interpret the research findings accurately and comprehensively.
To place the study in the broader context of existing literature.
To engage in critical thinking and analysis of the results.
To communicate the significance and implications of the study effectively.

How To Structure a Discussion

Follow these steps to draft a well-organized and effective discussion:

Now that you have a clear structure of your discussion section letâs move on to the writing phase.

The steps below will help you write an effective research paper discussion section:

Step 1: Summarize your Results

Start the discussion section by providing a brief reintroduction to your research question or hypothesis. This serves to set the stage for the discussion, reminding readers of the study's primary focus.

Next, proceed to summarize your results. Offer a concise overview of the main findings, highlighting the most relevant outcomes of your research. This lays the groundwork for the subsequent interpretation and analysis.

Step 2: Provide Interpretations

In this step, highlight why your findings matter and how they enhance our understanding of the research area. Use a mix of qualitative and quantitative techniques to comprehensively interpret results.

Here are some key points to keep in mind:

Explain the correlation, patterns, and relationships in your data.
Quantify these relations and clarify how they contribute to your study's understanding.
Assess if your results align with expectations and whether they support or challenge existing theories.
Relate your interpretations to past research and established theories, showcasing their challenges to existing knowledge.
If there are unexpected results, thoroughly explain them, explore reasons, and discuss their implications for the topic.

Organize your interpretations around themes, hypotheses, or research questions for a focused and structured discussion. Structure your interpretations based on the significance of findings or unexpected results to guide the reader through the crucial aspects of your study.

Step 3: Unpack the Implications

Unpacking the implications involves relating your findings to scholarly work. Discuss how your study aligns with or deviates from previous research from your literature review. It will showcase the academic context of your contributions.

Answer these questions:

Do your results confirm or contest existing theories? If supporting, what fresh insights do they bring? If challenging, what could be the reasons?
Are there practical applications of your findings?

Step 4: Discuss the Limitation

Limitations refer to factors that could potentially impact the accuracy, reliability, or scope of your study. They are aspects that were beyond your control or constraints within the research design.

Common Sources of Limitations

Limitations may arise due to various factors, such as the study's methodology, sample size, data collection tools, or external influences. Identifying these limitations is a crucial aspect of maintaining transparency in research.

How to Mention Limitations in the Discussion Section

Even the most well-conducted studies have limitations. Mentioning these limitations will enhance your research paper's credibility:

Clearly and honestly state the limitations of your study. Transparency builds credibility and demonstrates a thoughtful approach to the research process.
If there were limitations in your methodology (e.g., small sample size, survey design), discuss how these constraints might have affected the study's outcomes.
If data collection presented challenges (e.g., limited access, response bias), explain how these issues might have impacted the reliability of your results.
Acknowledge external factors beyond your control that might have influenced the study. This could include unforeseen events, changing societal norms, or evolving technologies.

Highlight limitations directly influencing your research problem or question for a concise and relevant discussion.

Step 5: Offer Recommendations

Having discussed the findings and limitations, it's now time to provide recommendations. These suggestions should arise from the insights gained during the study and serve as a guide for future studies.

How to Offer Recommendations

To offer recommendations keep in view the following points:

Base your recommendations on the insights discussed earlier. Consider what gaps or unanswered questions remain.
If applicable, recommend ways to address the limitations discussed in the study. Propose methodologies or approaches that could enhance future research.
Relate recommendations to practical applications whenever possible. Consider how future studies could provide actionable insights for real-world scenarios.
Offer tangible suggestions for further research. Provide clear directions and highlight specific variables, populations, or contexts that warrant exploration.

Discussion Writing Tips - DO'S & DONT'S

Here are some important tips to consider and some common mistakes to avoid when writing a discussion section for your research paper:

DO ensure that every point in your discussion directly relates back to your research questions or hypotheses. This maintains focus and relevance.
DO prioritize clarity in your writing. Use concise and straightforward language to communicate complex ideas, making them accessible to a broad audience.
DO acknowledge potential counterarguments or alternative explanations. This demonstrates a nuanced understanding of the topic and adds depth to your discussion.
DO use concrete examples to illustrate your points. This helps readers grasp the practical implications of your findings and enhances the overall understanding.
DO provide actionable recommendations for future studies. Give researchers clear directions and ideas for expanding on your work, contributing to the advancement of the field.
DON'T introduce new information in the discussion. Stick to summarizing, interpreting, and discussing the results obtained in the study without adding fresh data or concepts.
DON'T overgeneralize your findings. Be cautious not to make sweeping statements beyond the scope of your study or without sufficient evidence.
DON'T ignore or downplay limitations. Be transparent about the constraints of your study, acknowledging potential biases or areas where improvements could be made.
DON'T use jargon unnecessarily. While some field-specific terminology is essential, avoid excessive technical language that might confuse readers who are not familiar with the subject.
DON'T rush the conclusion of your discussion. Take the time to craft a thoughtful and conclusive summary that encapsulates the key takeaways and implications of your study.

Discussion Section Examples

If you're new to crafting research paper discussions, seeking examples can serve as a helpful guide to tailor your approach according to your paper's style and type.

Discussion For A Scientific Paper

Discussion For A Medical Research Paper

Example of Result And Discussion In Research Paper

Discussion in A Report

Qualitative Research Discussion Example

Wrapping up,

In this guide, we've explored the essential elements, steps, and provided examples to demystify the process.

By adhering to the outlined steps you ensure a well-rounded and insightful discussion. Always keep your research questions in focus, maintaining clarity and relevance.

Remember, discussions are not merely an endpoint but a springboard for future research. But if you find yourself struggling with the right syllables or structure for your discussion section, professional assistance is just a step away.

Our reliable writing service is here to support you with your academic writing needs. With our experienced team, you can navigate the complexities of crafting a stellar discussion with confidence.

Don't hesitate to reach out to our research paper writing service today!

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How to Write a Discussion Section | Tips & Examples

How to Write a Discussion Section | Tips & Examples

Published on 21 August 2022 by Shona McCombes . Revised on 25 October 2022.

The discussion section is where you delve into the meaning, importance, and relevance of your results .

It should focus on explaining and evaluating what you found, showing how it relates to your literature review , and making an argument in support of your overall conclusion . It should not be a second results section .

There are different ways to write this section, but you can focus your writing around these key elements:

Summary: A brief recap of your key results
Interpretations: What do your results mean?
Implications: Why do your results matter?
Limitations: What can’t your results tell us?
Recommendations: Avenues for further studies or analyses

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What not to include in your discussion section, step 1: summarise your key findings, step 2: give your interpretations, step 3: discuss the implications, step 4: acknowledge the limitations, step 5: share your recommendations, discussion section example.

There are a few common mistakes to avoid when writing the discussion section of your paper.

Don’t introduce new results: You should only discuss the data that you have already reported in your results section .
Don’t make inflated claims: Avoid overinterpretation and speculation that isn’t directly supported by your data.
Don’t undermine your research: The discussion of limitations should aim to strengthen your credibility, not emphasise weaknesses or failures.

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Start this section by reiterating your research problem and concisely summarising your major findings. Don’t just repeat all the data you have already reported – aim for a clear statement of the overall result that directly answers your main research question . This should be no more than one paragraph.

Many students struggle with the differences between a discussion section and a results section . The crux of the matter is that your results sections should present your results, and your discussion section should subjectively evaluate them. Try not to blend elements of these two sections, in order to keep your paper sharp.

The results indicate that …
The study demonstrates a correlation between …
This analysis supports the theory that …
The data suggest that …

The meaning of your results may seem obvious to you, but it’s important to spell out their significance for your reader, showing exactly how they answer your research question.

The form of your interpretations will depend on the type of research, but some typical approaches to interpreting the data include:

Identifying correlations , patterns, and relationships among the data
Discussing whether the results met your expectations or supported your hypotheses
Contextualising your findings within previous research and theory
Explaining unexpected results and evaluating their significance
Considering possible alternative explanations and making an argument for your position

You can organise your discussion around key themes, hypotheses, or research questions, following the same structure as your results section. Alternatively, you can also begin by highlighting the most significant or unexpected results.

In line with the hypothesis …
Contrary to the hypothesised association …
The results contradict the claims of Smith (2007) that …
The results might suggest that x . However, based on the findings of similar studies, a more plausible explanation is x .

As well as giving your own interpretations, make sure to relate your results back to the scholarly work that you surveyed in the literature review . The discussion should show how your findings fit with existing knowledge, what new insights they contribute, and what consequences they have for theory or practice.

Ask yourself these questions:

Do your results support or challenge existing theories? If they support existing theories, what new information do they contribute? If they challenge existing theories, why do you think that is?
Are there any practical implications?

Your overall aim is to show the reader exactly what your research has contributed, and why they should care.

These results build on existing evidence of …
The results do not fit with the theory that …
The experiment provides a new insight into the relationship between …
These results should be taken into account when considering how to …
The data contribute a clearer understanding of …
While previous research has focused on x , these results demonstrate that y .

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Even the best research has its limitations. Acknowledging these is important to demonstrate your credibility. Limitations aren’t about listing your errors, but about providing an accurate picture of what can and cannot be concluded from your study.

Limitations might be due to your overall research design, specific methodological choices , or unanticipated obstacles that emerged during your research process.

Here are a few common possibilities:

If your sample size was small or limited to a specific group of people, explain how generalisability is limited.
If you encountered problems when gathering or analysing data, explain how these influenced the results.
If there are potential confounding variables that you were unable to control, acknowledge the effect these may have had.

After noting the limitations, you can reiterate why the results are nonetheless valid for the purpose of answering your research question.

The generalisability of the results is limited by …
The reliability of these data is impacted by …
Due to the lack of data on x , the results cannot confirm …
The methodological choices were constrained by …
It is beyond the scope of this study to …

Based on the discussion of your results, you can make recommendations for practical implementation or further research. Sometimes, the recommendations are saved for the conclusion .

Suggestions for further research can lead directly from the limitations. Don’t just state that more studies should be done – give concrete ideas for how future work can build on areas that your own research was unable to address.

Further research is needed to establish …
Future studies should take into account …
Avenues for future research include …

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Home » Research Paper – Structure, Examples and Writing Guide

Research Paper – Structure, Examples and Writing Guide

Table of Contents

Research Paper

Definition:

Research Paper is a written document that presents the author’s original research, analysis, and interpretation of a specific topic or issue.

It is typically based on Empirical Evidence, and may involve qualitative or quantitative research methods, or a combination of both. The purpose of a research paper is to contribute new knowledge or insights to a particular field of study, and to demonstrate the author’s understanding of the existing literature and theories related to the topic.

Structure of Research Paper

The structure of a research paper typically follows a standard format, consisting of several sections that convey specific information about the research study. The following is a detailed explanation of the structure of a research paper:

The title page contains the title of the paper, the name(s) of the author(s), and the affiliation(s) of the author(s). It also includes the date of submission and possibly, the name of the journal or conference where the paper is to be published.

The abstract is a brief summary of the research paper, typically ranging from 100 to 250 words. It should include the research question, the methods used, the key findings, and the implications of the results. The abstract should be written in a concise and clear manner to allow readers to quickly grasp the essence of the research.

Introduction

The introduction section of a research paper provides background information about the research problem, the research question, and the research objectives. It also outlines the significance of the research, the research gap that it aims to fill, and the approach taken to address the research question. Finally, the introduction section ends with a clear statement of the research hypothesis or research question.

Literature Review

The literature review section of a research paper provides an overview of the existing literature on the topic of study. It includes a critical analysis and synthesis of the literature, highlighting the key concepts, themes, and debates. The literature review should also demonstrate the research gap and how the current study seeks to address it.

The methods section of a research paper describes the research design, the sample selection, the data collection and analysis procedures, and the statistical methods used to analyze the data. This section should provide sufficient detail for other researchers to replicate the study.

The results section presents the findings of the research, using tables, graphs, and figures to illustrate the data. The findings should be presented in a clear and concise manner, with reference to the research question and hypothesis.

The discussion section of a research paper interprets the findings and discusses their implications for the research question, the literature review, and the field of study. It should also address the limitations of the study and suggest future research directions.

The conclusion section summarizes the main findings of the study, restates the research question and hypothesis, and provides a final reflection on the significance of the research.

The references section provides a list of all the sources cited in the paper, following a specific citation style such as APA, MLA or Chicago.

How to Write Research Paper

You can write Research Paper by the following guide:

Choose a Topic: The first step is to select a topic that interests you and is relevant to your field of study. Brainstorm ideas and narrow down to a research question that is specific and researchable.
Conduct a Literature Review: The literature review helps you identify the gap in the existing research and provides a basis for your research question. It also helps you to develop a theoretical framework and research hypothesis.
Develop a Thesis Statement : The thesis statement is the main argument of your research paper. It should be clear, concise and specific to your research question.
Plan your Research: Develop a research plan that outlines the methods, data sources, and data analysis procedures. This will help you to collect and analyze data effectively.
Collect and Analyze Data: Collect data using various methods such as surveys, interviews, observations, or experiments. Analyze data using statistical tools or other qualitative methods.
Organize your Paper : Organize your paper into sections such as Introduction, Literature Review, Methods, Results, Discussion, and Conclusion. Ensure that each section is coherent and follows a logical flow.
Write your Paper : Start by writing the introduction, followed by the literature review, methods, results, discussion, and conclusion. Ensure that your writing is clear, concise, and follows the required formatting and citation styles.
Edit and Proofread your Paper: Review your paper for grammar and spelling errors, and ensure that it is well-structured and easy to read. Ask someone else to review your paper to get feedback and suggestions for improvement.
Cite your Sources: Ensure that you properly cite all sources used in your research paper. This is essential for giving credit to the original authors and avoiding plagiarism.

Research Paper Example

Note : The below example research paper is for illustrative purposes only and is not an actual research paper. Actual research papers may have different structures, contents, and formats depending on the field of study, research question, data collection and analysis methods, and other factors. Students should always consult with their professors or supervisors for specific guidelines and expectations for their research papers.

Research Paper Example sample for Students:

Title: The Impact of Social Media on Mental Health among Young Adults

Abstract: This study aims to investigate the impact of social media use on the mental health of young adults. A literature review was conducted to examine the existing research on the topic. A survey was then administered to 200 university students to collect data on their social media use, mental health status, and perceived impact of social media on their mental health. The results showed that social media use is positively associated with depression, anxiety, and stress. The study also found that social comparison, cyberbullying, and FOMO (Fear of Missing Out) are significant predictors of mental health problems among young adults.

Introduction: Social media has become an integral part of modern life, particularly among young adults. While social media has many benefits, including increased communication and social connectivity, it has also been associated with negative outcomes, such as addiction, cyberbullying, and mental health problems. This study aims to investigate the impact of social media use on the mental health of young adults.

Literature Review: The literature review highlights the existing research on the impact of social media use on mental health. The review shows that social media use is associated with depression, anxiety, stress, and other mental health problems. The review also identifies the factors that contribute to the negative impact of social media, including social comparison, cyberbullying, and FOMO.

Methods : A survey was administered to 200 university students to collect data on their social media use, mental health status, and perceived impact of social media on their mental health. The survey included questions on social media use, mental health status (measured using the DASS-21), and perceived impact of social media on their mental health. Data were analyzed using descriptive statistics and regression analysis.

Results : The results showed that social media use is positively associated with depression, anxiety, and stress. The study also found that social comparison, cyberbullying, and FOMO are significant predictors of mental health problems among young adults.

Discussion : The study’s findings suggest that social media use has a negative impact on the mental health of young adults. The study highlights the need for interventions that address the factors contributing to the negative impact of social media, such as social comparison, cyberbullying, and FOMO.

Conclusion : In conclusion, social media use has a significant impact on the mental health of young adults. The study’s findings underscore the need for interventions that promote healthy social media use and address the negative outcomes associated with social media use. Future research can explore the effectiveness of interventions aimed at reducing the negative impact of social media on mental health. Additionally, longitudinal studies can investigate the long-term effects of social media use on mental health.

Limitations : The study has some limitations, including the use of self-report measures and a cross-sectional design. The use of self-report measures may result in biased responses, and a cross-sectional design limits the ability to establish causality.

Implications: The study’s findings have implications for mental health professionals, educators, and policymakers. Mental health professionals can use the findings to develop interventions that address the negative impact of social media use on mental health. Educators can incorporate social media literacy into their curriculum to promote healthy social media use among young adults. Policymakers can use the findings to develop policies that protect young adults from the negative outcomes associated with social media use.

References :

Twenge, J. M., & Campbell, W. K. (2019). Associations between screen time and lower psychological well-being among children and adolescents: Evidence from a population-based study. Preventive medicine reports, 15, 100918.
Primack, B. A., Shensa, A., Escobar-Viera, C. G., Barrett, E. L., Sidani, J. E., Colditz, J. B., … & James, A. E. (2017). Use of multiple social media platforms and symptoms of depression and anxiety: A nationally-representative study among US young adults. Computers in Human Behavior, 69, 1-9.
Van der Meer, T. G., & Verhoeven, J. W. (2017). Social media and its impact on academic performance of students. Journal of Information Technology Education: Research, 16, 383-398.

Appendix : The survey used in this study is provided below.

Social Media and Mental Health Survey

How often do you use social media per day?
Less than 30 minutes
30 minutes to 1 hour
1 to 2 hours
2 to 4 hours
More than 4 hours
Which social media platforms do you use?
Others (Please specify)
How often do you experience the following on social media?
Social comparison (comparing yourself to others)
Cyberbullying
Fear of Missing Out (FOMO)
Have you ever experienced any of the following mental health problems in the past month?
Do you think social media use has a positive or negative impact on your mental health?
Very positive
Somewhat positive
Somewhat negative
Very negative
In your opinion, which factors contribute to the negative impact of social media on mental health?
Social comparison
In your opinion, what interventions could be effective in reducing the negative impact of social media on mental health?
Education on healthy social media use
Counseling for mental health problems caused by social media
Social media detox programs
Regulation of social media use

Thank you for your participation!

Applications of Research Paper

Research papers have several applications in various fields, including:

Advancing knowledge: Research papers contribute to the advancement of knowledge by generating new insights, theories, and findings that can inform future research and practice. They help to answer important questions, clarify existing knowledge, and identify areas that require further investigation.
Informing policy: Research papers can inform policy decisions by providing evidence-based recommendations for policymakers. They can help to identify gaps in current policies, evaluate the effectiveness of interventions, and inform the development of new policies and regulations.
Improving practice: Research papers can improve practice by providing evidence-based guidance for professionals in various fields, including medicine, education, business, and psychology. They can inform the development of best practices, guidelines, and standards of care that can improve outcomes for individuals and organizations.
Educating students : Research papers are often used as teaching tools in universities and colleges to educate students about research methods, data analysis, and academic writing. They help students to develop critical thinking skills, research skills, and communication skills that are essential for success in many careers.
Fostering collaboration: Research papers can foster collaboration among researchers, practitioners, and policymakers by providing a platform for sharing knowledge and ideas. They can facilitate interdisciplinary collaborations and partnerships that can lead to innovative solutions to complex problems.

When to Write Research Paper

Research papers are typically written when a person has completed a research project or when they have conducted a study and have obtained data or findings that they want to share with the academic or professional community. Research papers are usually written in academic settings, such as universities, but they can also be written in professional settings, such as research organizations, government agencies, or private companies.

Here are some common situations where a person might need to write a research paper:

For academic purposes: Students in universities and colleges are often required to write research papers as part of their coursework, particularly in the social sciences, natural sciences, and humanities. Writing research papers helps students to develop research skills, critical thinking skills, and academic writing skills.
For publication: Researchers often write research papers to publish their findings in academic journals or to present their work at academic conferences. Publishing research papers is an important way to disseminate research findings to the academic community and to establish oneself as an expert in a particular field.
To inform policy or practice : Researchers may write research papers to inform policy decisions or to improve practice in various fields. Research findings can be used to inform the development of policies, guidelines, and best practices that can improve outcomes for individuals and organizations.
To share new insights or ideas: Researchers may write research papers to share new insights or ideas with the academic or professional community. They may present new theories, propose new research methods, or challenge existing paradigms in their field.

Purpose of Research Paper

The purpose of a research paper is to present the results of a study or investigation in a clear, concise, and structured manner. Research papers are written to communicate new knowledge, ideas, or findings to a specific audience, such as researchers, scholars, practitioners, or policymakers. The primary purposes of a research paper are:

To contribute to the body of knowledge : Research papers aim to add new knowledge or insights to a particular field or discipline. They do this by reporting the results of empirical studies, reviewing and synthesizing existing literature, proposing new theories, or providing new perspectives on a topic.
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Published: 15 April 2024

Age-specific nasal epithelial responses to SARS-CoV-2 infection

Maximillian N. J. Woodall 1 na1 ,
Ana-Maria Cujba 2 na1 ,
Kaylee B. Worlock ORCID: orcid.org/0000-0002-5656-7634 3 na1 ,
Katie-Marie Case 1 ,
Tereza Masonou 1 ,
Masahiro Yoshida ORCID: orcid.org/0000-0002-3521-5322 3 ,
Krzysztof Polanski ORCID: orcid.org/0000-0002-2586-9576 2 ,
Ni Huang 2 ,
Rik G. H. Lindeboom ORCID: orcid.org/0000-0002-3660-504X 2 ,
Lira Mamanova 2 ,
Liam Bolt ORCID: orcid.org/0000-0001-7293-0774 2 ,
Laura Richardson ORCID: orcid.org/0000-0002-8075-3816 2 ,
Batuhan Cakir 2 ,
Samuel Ellis 1 ,
Machaela Palor ORCID: orcid.org/0000-0003-4276-5346 1 ,
Thomas Burgoyne ORCID: orcid.org/0000-0002-8428-720X 4 , 5 ,
Andreia Pinto ORCID: orcid.org/0000-0002-0840-6844 5 ,
Dale Moulding ORCID: orcid.org/0000-0002-1431-7047 1 ,
Timothy D. McHugh ORCID: orcid.org/0000-0003-4658-8594 6 ,
Aarash Saleh 7 ,
Eliz Kilich ORCID: orcid.org/0000-0003-0928-8293 3 , 8 ,
Puja Mehta ORCID: orcid.org/0000-0001-9459-9306 3 , 8 ,
Chris O’Callaghan 1 ,
Jie Zhou 9 ,
Wendy Barclay ORCID: orcid.org/0000-0002-6413-2454 9 ,
Paolo DeCoppi ORCID: orcid.org/0000-0002-1659-0207 1 , 10 ,
Colin R. Butler 10 , 11 ,
Mario Cortina-Borja 1 ,
Heloise Vinette 1 ,
Sunando Roy 1 ,
Judith Breuer ORCID: orcid.org/0000-0001-8246-0534 1 ,
Rachel C. Chambers ORCID: orcid.org/0000-0003-1370-9417 3 ,
Wendy E. Heywood 1 ,
Kevin Mills 1 ,
Robert E. Hynds 11 , 12 ,
Sarah A. Teichmann ORCID: orcid.org/0000-0002-6294-6366 2 , 13 na2 ,
Kerstin B. Meyer ORCID: orcid.org/0000-0001-5906-1498 2 na2 ,
Marko Z. Nikolić ORCID: orcid.org/0000-0001-6304-6848 3 , 8 na2 &
Claire M. Smith ORCID: orcid.org/0000-0002-8913-0009 1 na2

Nature Microbiology ( 2024 ) Cite this article

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Mechanisms of disease
Molecular biology

Children infected with SARS-CoV-2 rarely progress to respiratory failure. However, the risk of mortality in infected people over 85 years of age remains high. Here we investigate differences in the cellular landscape and function of paediatric (<12 years), adult (30–50 years) and older adult (>70 years) ex vivo cultured nasal epithelial cells in response to infection with SARS-CoV-2. We show that cell tropism of SARS-CoV-2, and expression of ACE2 and TMPRSS2 in nasal epithelial cell subtypes, differ between age groups. While ciliated cells are viral replication centres across all age groups, a distinct goblet inflammatory subtype emerges in infected paediatric cultures and shows high expression of interferon-stimulated genes and incomplete viral replication. In contrast, older adult cultures infected with SARS-CoV-2 show a proportional increase in basaloid-like cells, which facilitate viral spread and are associated with altered epithelial repair pathways. We confirm age-specific induction of these cell types by integrating data from in vivo COVID-19 studies and validate that our in vitro model recapitulates early epithelial responses to SARS-CoV-2 infection.

Distinct airway epithelial immune responses after infection with SARS-CoV-2 compared to H1N1

Helen Stölting, Laury Baillon, … Clare M. Lloyd

Delayed induction of type I and III interferons mediates nasal epithelial cell permissiveness to SARS-CoV-2

Catherine F. Hatton, Rachel A. Botting, … Christopher J. A. Duncan

SARS-CoV-2 infection induces the dedifferentiation of multiciliated cells and impairs mucociliary clearance

Rémy Robinot, Mathieu Hubert, … Lisa A. Chakrabarti

Despite effective vaccines, age remains the single greatest risk factor for COVID-19 mortality. Children infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rarely develop severe disease 1 , while the mortality in infected people over 85 years is currently as high as 1 in 10 (ref. 2 ). Nasal epithelial cells (NECs) are the primary target of SARS-CoV-2 (refs. 3 , 4 ), and understanding their viral response is crucial as infection of upper airway cells can progress distally 5 , 6 , leading to diffuse alveolar injury with respiratory failure and long-term complications including lung fibrosis 7 .

Initially, it was thought that higher viral entry factor expression of angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in adults could explain increased severity, but such differences between children and adults remain uncertain 8 , 9 . Children may alternatively be protected by a pre-activated antiviral state in the upper airways 9 , 10 , but this does not fully explain the increased risk with increasing age. In addition, most in vivo studies so far were unable to identify early cellular responses, since in almost all cases the exact time of infection was unknown, symptom onset was variable and research sampling usually occurred only a few days after testing positive for SARS-CoV-2 (ref. 9 ).

Here we investigated the effects of early SARS-CoV-2 infection on human NECs from healthy children (0–11 years), adults (30–50 years) and older adults (>70 years). NEC were cultured at an air-liquid interface (ALI) and either subjected to mock infection or infected with SARS-CoV-2 for up to 3 days. This setup was used to examine epithelial-intrinsic differences in function, viral replication, gene and protein expression. We reveal age-specific epithelial responses, independent of immune cells, with a strong interferon (IFN) response in infected paediatric goblet inflammatory cells, and the appearance of older adult basaloid-like cells that sustain viral replication and are associated with fibrotic signalling pathways.

Differences in the cellular landscape of NECs with age

We first investigated the cellular composition of NECs at different ages using single-cell RNA sequencing (scRNA-seq; Fig. 1a ). We analysed a dataset of 139,598 cells and identified 24 distinct epithelial cell types or states (Fig. 1b and Extended Data Fig. 1a–c ). These included basal (KRT5 hi ), secretory (SCGB1A1 hi , MUC5AC+) and ciliated (CCDC40+) cells (markers in Extended Data Fig. 1d ). Basal cells encompassed various subpopulations, such as basal, cycling basal, hillock, basal|EMT (associated with epithelial–mesenchymal transition (EMT)) and basaloid-like cells enriched in fibrotic lungs 11 . The second domain includes secretory, goblet and squamous cells, each expressing different secretory proteins and genes related to mucosal defence. The third domain comprised ciliated cells, which were further divided into two clusters on the basis of gene expression patterns associated with cilium organization. Comparison to published nasal COVID-19 datasets 9 , 12 confirmed the accuracy of our cell annotations including ionocytes and hillock cells (Extended Data Fig. 1e,f ).

a , Schematic of method and model used to study SARS-CoV-2 infection of paediatric (P, <12 years), adult (A, 30–50 years) and older adult (O, >70 years) nasal epithelial cells. b , UMAP visualization of annotated airway epithelial cells. Cell numbers per cell type are shown in parentheses. Dotted lines indicate the three principal cell domains these fall within: KRT5 high (KRT5 hi ), SCGB1A high (SCGB1A hi ) and ciliated/other. UMAP shows the entire single-cell sequencing (scRNA-seq) dataset, including SARS-CoV-2 and mock-infected NEC cultures across all three timepoints and ages ( n = P3, A4, O4). c , Percentage of annotated airway epithelial cells with respect to age in baseline (non-infected) NEC cultures and following label transfer to an in vivo dataset of nasal brushings from age-matched donors from ref. 9 (data shown as a percentage cells in the three principal cell domains found in each age group). d , SARS-CoV-2 entry factor protein expression per culture type determined by Western blot. Comparisons of ACE2 and TMPRSS2 protein levels normalized to GAPDH were made using the Wilcoxon test. Individual values plotted for each participant, indicated by dots ( n = P9, A7, O8). e , SARS-CoV-2 entry factor gene expression by scRNA-seq. SARS-CoV-2 entry factor gene expression per cell type calculated on the basis of absolute cell numbers, with the average expression of ACE2 and TMPRSS2 indicated by colour. Dot size corresponds to the number of cells expressing ACE2 and TMPRSS2 in respective age groups in the mock condition. f , SARS-CoV-2 RNA viral reads (grey dots, per cell; red dots, per donor) as determined by viral transcript counts (encoding for the full viral genome) per nucleotide per 500 cells (grey dots) or nucleotide per 500 cells per donor (red dots) within each age group. Pairwise comparisons between donors’ age groups were performed using two-sided Wilcoxon rank-sum tests; NS, not significant. g , SARS-CoV-2 viral reads were detected within the scRNA-seq dataset (Infected condition only) at 24 (top) and 72 h (bottom) post infection, shown by cell type and age groups, with dot size and colour indicative of the percentage of cells with detectable viral reads and average reads per cell, respectively. h , Representative maximum intensity z -projections of confocal images (left) of NEC cultures immunolabelled against cilia (cyan, tubulin), dsRNA (yellow) and basal cells (KRT5, white) with DAPI (blue) and phalloidin (magenta) to indicate the nucleus and actin filaments, respectively. Scale bar, 50 μm. Representation of dsRNA signal alone for each section is indicated in red adjacent to respective maximal projections, with the value of spread given on each panel. Summarized on the bar graph to the right (mean ± s.d.), subjected to one-way analysis of variance (ANOVA) with Tukey’s multiple comparisons test. Individual values are shown for each donor ( n = P8, A5, O6). A representative orthogonal section is given (bottom right) to indicate location of dsRNA within infected NECs. i , j , Transmission electron micrographs of epithelial cell types infected with SARS-CoV-2, with selected areas of interest shown at a higher magnitude for each; i , ciliated cells (left), goblet cell (middle), transit (right) and j , ciliated 2 cell types. Panels show components of interest within each cell type, denoted by arrows: white arrows, SARS-CoV-2; green arrows, cilia; blue arrows, secretory mucin granules; viral particles false-coloured with red to aid visualization. k , SARS-CoV-2 protein abundance in apical fluid (extracellular) and cell lysates (intracellular) from SARS-CoV-2-infected NECs for 72 h p.i. as determined by mass spectrometry. Data are shown as mean abundance of protein (dot size) and mean fold change (FC) in protein abundance per donor from mock-infected NECs (colour, age group) ( n = P5, A5, O5). l , Infectious viral titres in combined cell lysate and apical fluid of SARS-CoV-2 nasal epithelial cells from paediatric, adult and older adult donors as determined by plaque assays (mean ± s.d.). Two-way ANOVA with Tukey’s multiple comparisons test. Individual values are shown for each donor ( n = P13, A8, O8). Lines in box and whisker plots ( d , f ) indicate median, interquartile range (IQR) and minimum to maximum of the distribution.

Source data

Interestingly, we observed age-related differences in cell-type proportions in healthy control cultures, with a higher abundance of basal/progenitor subtypes in adult versus paediatric cultures (Fig. 1c and Extended Data Fig. 1g ), mirroring an in vivo nasal epithelial dataset 9 (Extended Data Fig. 1e,f ). All age groups exhibited similar apical differentiation, mucus and tubulin expression (Extended Data Fig. 1h ), and ciliary activity (Extended Data Fig. 2a,b ). There was no substantial difference in ciliary beat frequency or cellular motility with age (Extended Data Fig. 2a,c ). However, NEC cultures from older adult donors were thicker (mean ± s.d. 40 ± 18 µm) than paediatric cultures (20 ± 10 µm; P = 0.02) (Extended Data Fig. 2d ) with a distinct spiral morphology typical of NEC cultures (Extended Data Fig. 2e ), though this had no effect on the integrity of the epithelial barrier (Extended Data Fig. 2f ).

The most notable difference in paediatric cultures was an increase of goblet cell types, particularly the goblet 2 cells (Extended Data Fig. 1g ). This shift in cell state from secretory (higher in KRT5 ) to goblet (higher in BPIFA1) cells was not observed in adult and older adult cultures. Importantly, while the total protein levels of SARS-CoV-2 entry factors 13 did not vary with age (Fig. 1d ), paediatric cultures showed higher mRNA expression of TMPRSS2 and ACE2 in goblet cells (Fig. 1e ). In adult and older adult cultures, these markers were predominantly expressed in secretory and basal 2 cell types (Fig. 1e ), suggesting a shift in susceptibility to viral infection from goblet to secretory cell types with age. Other viral entry factors, BSG , CTSL , NRP1 , NRP2 and FURIN showed the same trend as ACE2 and TMPRSS2 (Extended Data Fig. 2g ).

Increased virus production in infected older adult NECs

To determine differences in viral replication between age groups, NEC cultures were infected with an early-lineage SARS-CoV-2 isolate (hCoV-19/England/2/2020; 4 × 10 4 plaque forming units (p.f.u.) per well (approximate multiplicity of infection (MOI) of 0.01 p.f.u. per cell)). Over a 5-day infection period, SARS-CoV-2 replication increased and then peaked at 72 h post infection (p.i.) (Extended Data Fig. 3a,b ); therefore, all subsequent investigations were completed before this timepoint. The total number of viral reads increased with time but did not differ between age groups (Fig. 1f ), with fewer cell types infected (showing >0 viral reads) in paediatric (3/24 cell types) versus adult and older adult cultures (7/24 and 11/24 cell types, respectively) at 24 h p.i. (Fig. 1g and Extended Data Fig. 3c–e ) and a wider range at 72 h p.i. in all age groups (Fig. 1g ). We also measured total viral spread (measured as %dsRNA+ signal coverage) by immunofluorescent analysis at 72 h p.i., which was greater in older adult (mean ± s.d. 16.1% ± 9.5) than in paediatric cultures (3.8% ± 3.1) (Fig. 1h and Supplementary Fig. 1 ). Overall, ciliated 2 and transit epi 2 cells had the highest proportion of viral reads (Fig. 1g ). Strikingly, goblet cell types appeared more infected in paediatric cultures, while adult and older adult cultures showed highest viral reads in secretory cell types (Fig. 1g and Extended Data Fig. 3c–e ). Cells expressing the highest viral reads displayed high ACE2 ( R 2 = 0.71) and TMPRSS2 ( R 2 = 0.57) expression (Extended Data Fig. 3f,g ). Transmission electron microscopy (TEM) demonstrated the presence of viral particles (red) in cells possessing both mucin-containing secretory granules and cilia (Fig. 1i,j , and Supplementary Figs. 2 and 3 ).

Key differences across the age groups were greater apical localization of the SARS-CoV-2 spike protein (Extended Data Fig. 3f ), greater abundance of intracellular and apical secreted SARS-CoV-2 proteins (Fig. 1k ) and higher levels of infectious particles in older adult than in with paediatric cultures, with a significant ( P = 0.04) >800-fold higher titre in older adult (mean ± s.d. 1.64 × 10 7 ± 3.94 × 10 7 p.f.u. per well; n = 8) than in paediatric cultures (1.71 × 10 4 ± 3.20 × 10 4 p.f.u. per well; n = 13) at 72 h p.i. (Fig. 1l and Extended Data Fig. 4i ). These findings support the conclusion that SARS-CoV-2-infected older adult NECs translate more viral protein and generate more replication-competent viruses compared with paediatric cells.

SARS-CoV-2 infection induces age-specific effects

We next profiled the phenotypic effects of infection on epithelial cells, using live cell microscopy, immunofluorescence staining, proteomics and gene expression analysis, and compared these across the age groups.

Overall, we found that compared to uninfected cultures, SARS-CoV-2-infected adult ( P < 0.05, n = 5) and older adult ( P < 0.001, n = 7) cultures had decreased culture thickness (Fig. 2a,b and Extended Data Fig. 4a ) and epithelial integrity ( P < 0.03, n = 7; Fig. 2c ), with no change in adherens junction protein expression (Extended Data Fig. 4b ). This decrease in culture thickness was accompanied by an increase in basal cell mobilization ( P < 0.03, n = 7; Fig. 2d and Extended Data Fig. 4c,d ) and epithelial escape (cell protrusion) from the pseudostratified culture in older adult cultures (Fig. 2a,e ). Some protruded cells carried viral particles (Fig. 2f ) and expressed the SARS-CoV-2 spike protein (Fig. 2g ) and others were shown to completely detach from the pseudostratified epithelium on the apical surface of the culture (Fig. 2h and Extended Data Fig. 4e ). Ultrastructural changes such as endocytosis of cilia basal bodies and sloughing of ciliated cells were observed in all age groups (Supplementary Fig. 3 ). However, there was no significant loss of ciliated cells or changes in ciliary beat frequency (Extended Data Fig. 5a–c ), or entry factor protein expression within 72 h of infection (Extended Data Fig. 5d ).

a , Representative orthogonal views of the z -stacks showing the thickness (white dashed arrow) and morphology of fixed paediatric, adult and older adult mock- or SARS-CoV-2-infected NECs at 72 h p.i. Sections were immunolabelled against cilia (cyan, tubulin), F-actin (magenta, phalloidin), DAPI (blue), SARS-CoV-2 S protein (yellow) and cytokeratin 5 (white, KRT5+). Solid white arrows indicate cells protruding from the apical surface (as quantified further in e ). Scale bar, 50 μm. b , Epithelial thickness was further measured and quantified, and subjected to a two-way ANOVA with Sidak’s multiple comparison test ( n = P9, A5, O7). c , Epithelial integrity, as measured by trans-epithelial electrical resistance (TEER) (Ω × cm 2 ) from 72 h p.i. mock- or SARS-CoV-2-infected NECs ( n = P11, A4, O7), subjected to multiple paired t -tests. d , Quantification of non-basal KRT5+ cells (for example, KRT5+ cells above and not touching the basal membrane) as a measure of basal cell mobilization, with age and infection (mock vs infection). Calculated using a cross-section of fixed NECs at 72 h p.i. ( n = P7, A5, O5), subjected to two-way ANOVA with Tukey’s multiple comparisons test. See Extended Data Fig. 4c,d for more details for analysis. e , Cell protrusion analysis, calculated by counting the number of nuclei (blue, indicated by white solid arrows in a ) above apical epithelial membrane (magenta) per section per donor. Data shown as mean ± s.d. ( n = P7, A5, O6), subjected to one-way ANOVA with Tukey’s multiple comparisons test. f , Transmission electron micrograph of protruding epithelial cell type, heavily burdened with SARS-CoV-2 virions (red) at 72 h p.i. Scale bar, 2 μm. g , Representative images of immunofluorescence staining for cells that have escaped the pseudostratified position and reside above the apical membrane, as stained in a . Of note here: SARS-CoV-2 spike (yellow) and KRT5 (white). Image 3D-rendered (left) using Imaris (Bitplane) with Blend filter; scale bar, 60 µm. Scale bar for all other images: 5 µm, rendered in ImageJ in right bottom panel, showing a histogram of distance vs fluorescence intensity for DAPI, KRT5 and SARS-CoV-2 spike staining for a single Z -slice indicated by purple dotted line. h , Transmission electron micrograph of epithelial cell shedding (white arrows) at 72 h p.i. with SARS-CoV-2. i , j , UMAP representation of the results from Milo differential abundance (DA) testing (left plot) with nodes showing cell neighbourhoods and Beeswarm plot (right plot) showing the log(FC) observed when comparing SARS-CoV-2-infected versus mock conditions in paediatric i , and older adults j , with a significant enrichment of goblet 2 inflammatory cells and basaloid-like 2 cells, respectively, observed with infection. Beeswarm plot shows the distribution of log(fold change) across annotated cell clusters when comparing SARS versus mock groups, with cell types ranked on the basis of those with the highest fold change. Grey is non-significant, red is significantly increased, blue is significantly decreased at 10% FDR. k , UMAP visualization of annotated epithelial cells from lower and upper airways of 8 in vivo integrated single-cell datasets. Cell numbers per cell type are shown in parentheses. l , m , Graph comparing the frequency of ( l ) goblet inflammatory and ( m ) basaloid-like 2 cells normalized to the total number of cells per donor. Each dot represents the ratio of the number of cells multiplied by 1,000 to the total cells contributed from one donor and are coloured on the basis of age_status group. Healthy dataset n = P49, A45, O46; COVID-19 dataset n = P41, A58, O116. Statistical analysis was performed on the normalized proportions using zero-inflated Poisson models using the gamlss package in R. Boxplots show the median and IQR, plus the minimum and maximum value distribution. Note the large frequency of donors with zero incidence.

Using Milo 14 , we tested for differential cell state abundance following infection and whether this varied with age. In paediatric cultures, the most significant change was the emergence of goblet 2 inflammatory cells, which were not present in uninfected paediatric cultures (Fig. 2i and Extended Data Fig. 5e,f ). There was a decrease in basal, secretory and goblet cell populations, while the frequency of transit epi 2 and terminally differentiated goblet cells increased (that is, goblet 2 inflammatory) (Fig. 2i and Extended Data Fig. 6e,f ).

The goblet 2 inflammatory cell type is strongly associated with type I IFN signalling, with higher levels of CXCL10 , IFIT1 and IFIT3 markers than other goblet cell subtypes (Extended Data Fig. 1d ). While goblet inflammatory cells have previously been seen in vivo 9 , it is interesting that this inflammatory phenotype is epithelial cell-intrinsic and independent of immune cells that are not present in our cultures. We later (see next section) explore the impact of this on viral replication and spread.

The biggest and consistent change in infected older adult cultures was an increase in basal ( KRT5 hi ) cell populations, indicating an older adult-specific mobilization (proliferation) of progenitor cells following SARS-CoV-2 infection (Fig. 2j , adult dataset shown in Extended Data Fig. 5f,g ) and an expansion of basaloid-like 2 cells (Fig. 2j and Extended Data Fig. 5f ). These recently identified cells are characterized by markers associated with tissue injury and fibrosis ( ITGB6 , ITGB1 , ITGAV , ITGB8 , VIM , TGFB1 ) (Extended Data Fig. 1d ). In healthy epithelial tissue, including skin and lung, integrin beta 6 ( ITGB6 ) mRNA is virtually undetectable 15 , but its expression has been reported to be considerably upregulated during wound healing 16 , tumorigenesis and fibrosis 17 . The presence of these ITGB6 + cells is a major finding as they may be involved in the exacerbation of disease in older adults.

Pseudotime trajectory analysis suggested that goblet 2 inflammatory cells (Extended Data Fig. 2h ) and basaloid-like 1 cells (Extended Data Fig. 2j ) are terminal cell states, differentiating from goblet 2 PLAU+ (Extended Data Fig. 2i ) and Basal|EMT cells (Extended Data Fig. 2k ), respectively, with ciliated 1 cells seen as a third end state (Extended Data Fig. 5h )

In vivo patient validation of induced cell states

To confirm the existence of deregulated cell states in vivo, we performed an integration of 8 scRNA-seq datasets comprising 577,243 cells, spanning upper and lower airways from paediatric (0–18 years), adult (19–50 years), and older adults (51–90 years) that are either healthy or COVID-19 patients 9 , 10 , 12 , 18 , 19 , 20 , 21 , 22 (Fig. 2k and Extended Data Fig. 6a–c ). We identified common epithelial clusters by marker genes (Extended Data Fig. 6c ). Goblet inflammatory cells were induced in response to SARS-CoV-2 across all age groups, with the highest abundances in paediatric COVID-19 and older adult COVID-19 cohorts (Fig. 2l and Extended Data Fig. 6b ). We note that in the older adult COVID-19 cohort, a single donor (mild disease, early post-symptom samples) contributed 82% of all goblet inflammatory cells (Fig. 2l ). Thus, the induction of this cluster is most robust in the paediatric cohort. In the in vivo dataset, we also identified a basaloid-like 2 cell cluster enriched across all COVID-19 patients, which were most abundant in older adult COVID-19 patients across multiple donors (Fig. 2m and Extended Data Fig. 6c ), confirming our in vitro studies. Basaloid-like 2 cells also had the highest increase in fibrosis patients (both idiopathic pulmonary fibrosis and other pulmonary fibrosis), as previously reported 11 , 23 (Extended Data Fig. 6c ).

Stronger interferon response in paediatric cultures

As described, SARS-CoV-2 infection is associated with strong interferon responses, which were particularly apparent in paediatric goblet 2 inflammatory NECs but absent in mock-infected cultures and rare in infected older age groups (proportion of total goblet 2 inflammatory cells from NEC cultures: paediatric = 1,455/1,578, adult = 90/1,578, older adult = 33/1,578) (Extended Data Fig. 1g ). These cells exhibited high levels of interferon-stimulated genes (ISGs), associated with both type I and II interferon signalling (Fig. 3a,b and Extended Data Fig. 7a,b ), and were previously shown to reduce COVID-19 severity 10 , 24 . In addition, paediatric cultures-secreted proteins also showed an association with epithelial barrier and humoral immune response pathways (Extended Data Fig. 7c–e ).

a , UMAP visualization of expression of differentially expressed genes in goblet 2 inflammatory cells. Gene expression is shown in log1p scale. b , Scores of gene ontology (GO) term gene signatures for the terms: response to type 1 interferon ( GO:0035455 or GO:0034340 ) and type 2 interferon ( GO:0034341 ) across cell types. Scores were calculated with Scanpy as the average expression of the signature genes subtracted with the average expression of randomly selected genes from bins of corresponding expression values. Each dot is a cell. c , SARS-CoV-2 entry factor gene expression per cell type calculated on the basis of absolute cell numbers with the average expression of TMPRSS2 (top) and ACE2 (bottom) indicated by colour. Dot size corresponds to infected number of cells expressing TMPRSS2 and ACE2 in respective age groups in the mock (all timepoints) and SARS-CoV-2 (all timepoints) infected condition. d , Volcano plot showing differential gene expression between goblet 2 inflammatory and their precursor goblet 2 PLAU+ cells, with a total of 478 variables. Of note were several genes associated with an interferon response (for example, IFI6 , IFITM1 , IFIT1 , IFIT2 and ISG15 ) and SARS-CoV-2 viral replication (highlighted in red) which were significantly enriched within the paediatric goblet 2 inflammatory cells. The colours indicate the genes that have adjusted P values ≤0.05 (blue), a log 2 fold-change ≥1 or ≤−1 (green), or remain unchanged (grey). The dashed horizontal line signals statistical significance threshold (adjusted P values ≤0.05). Two vertical lines show the threshold of log 2 fold-change ≥0.5 and ≤−0.5. e , Visualization of MX1 protein-expressing cells. Maximum intensity projection images of immunofluorescence staining for F-actin (white, phalloidin), MX1 (green), SARS-CoV-2 S protein (red), with DAPI (blue) in composite image. An orthogonal view of the z -stacks is given in the bottom panel. Example given is a SARS-CoV-2-infected paediatric culture at 72 h p.i. Scale bar, 50 µm. f , Fold change in the gene expression in selected IFN genes across all cell types in SARS-CoV-2-infected NECs compared to mock infections in the single-cell datasets. Shown at each timepoint and broken down by age group. Where no expression was seen in the mock infection conditions, fold change was capped at 3 (red). Grey highlights genes that were absent in both conditions. g , Level (pg ml −1 ) of interferon protein (IFNA, IFNG and IFNL) within the apical supernatant between SARS-CoV-2 and mock-infected NECs. Two-way paired t -test. * P = 0.05, ** P < 0.01. ( n = P9, O9). h , Representative immunofluorescence images of inflammatory goblet cell markers at 72 h p.i. with SARS-CoV-2. Maximum intensity projection images of immunofluorescence staining in fixed paediatric NECs. Red, DAPI; white, IFNL1; blue, BPIFA1; cyan, SARS-CoV-2 spike (S) protein. i , Higher magnification image of that shown in h with white IFNL1; blue, BPIFA1 (white arrows annotate inflammatory goblet cells). j , Co-localization plot for BPIFA1 and SARS-CoV-2 S protein.

The precursors of goblet inflammatory cells are goblet 2 PLAU+ cells (Extended Data Fig. 2i ) which expressed high levels of TMPRSS2 and ACE2 (Fig. 3c ), suggesting that the virus targeted these cells and induced the generation of goblet inflammatory cells, which again expressed high levels of entry receptors and could thus be the target for further infection. This is supported by high viral reads and high ISG expression specific to this subtype (Fig. 3d ). Coexpression of viral spike protein and the interferon-induced gene MX1 was confirmed at the protein level in our paediatric cultures (Fig. 3e ). Induction of interferon responsive genes appears to be at least partly autocrine since paediatric inflammatory cells transcribed IFNL1 , IFNL2 and IFNA1 genes (Fig. 3f and Extended Data Fig. 7c ). When comparing the ISG response across all cell types and ages, it is apparent that by 72 h p.i. paediatric cultures express more interferon genes (Fig. 3f ), a difference that was validated at the protein level (Fig. 3g ). Furthermore, immunofluorescence staining demonstrated the co-localization ( R 2 = 0.76) of IFNL1 with the goblet 2 inflammatory cell marker BPIFA1 (Fig. 3h,i ).

Goblet inflammatory cells may restrict viral replication

In paediatric cultures, despite high viral reads, the production of infectious virions is lower than in older adult cultures (Fig. 1l ). Examining the distribution of viral reads, we found that viral transcription in paediatric ciliated cells predominantly occurred towards the 3’ end, indicating active viral replication (Fig. 4a ). However, in paediatric goblet 2 inflammatory cells, viral reads were highest near the 5’ end, suggesting failed viral replication (Fig. 4a and Extended Data Fig. 8a–c ). It was concluded that this bias towards the 3’ end was not a technical artefact due to the introduction of the spike-in primer to increase the detection of viral reads, as SARS-CoV-2 reads were successfully amplified without biasing viral distribution (Extended Data Fig. 8d–f ). Moreover, using deep viral sequencing, we found that non-canonical subgenomic SARS-CoV-2 RNAs (sgRNA), particularly spike and ORF7a sgRNA, were more abundant ( P = 0.042) in paediatric and adult samples than in older adult samples (Fig. 4b,c ). These non-canonical sgRNAs can result in defective viral genomes and have been associated with increased interferon production 25 . Paediatric cultures also exhibited more low-frequency and fixed mutations in viral genomes (Fig. 4d and Extended Data Fig. 8g ), particularly before the RNA-dependent RNA polymerase (RdRp) (that is, <16 kb; Fig. 4e ). These findings suggest that there is greater pressure on the virus to mutate in younger cultures, possibly due to the production of defective viral genomes by goblet 2 inflammatory cells (Fig. 4f ). In addition, ultrastructural observations revealed fewer viral particles in paediatric goblet cells than in heavily burdened neighbouring ciliated cells (Fig. 4g and Supplementary Fig. 2 ). Our findings indicate that paediatric goblet inflammatory cells may be responsible for the discrepancy between viral reads and infectious particles.

a , Coverage plot of viral reads aligned to SARS-CoV-2 genome from paediatric ciliated 2 (top) and goblet 2 inflammatory (middle) cells at 72 h p.i. Bottom panel shows the genomic organization of SARS-CoV-2 as drawn using Biorender.com . The sequencing depth was computed for each genomic position for each condition. b , Boxplot depicting the sgRPTL normalized counts for sgRNA abundances across age groups using unpaired t -test. c , The mean ± s.d. distribution of these sgRPTL counts across all genes in paediatric (green) and older adult (brown) NEC cultures, subjected to two-way ANOVA with Sidak’s multiple comparisons test ( n = P5, O5). d , Left: frequency of genomic mutations observed in different regions of the SARS-CoV-2 genome. Right: the position and whether an amino acid change was generated from that mutation. Data were generated from 72 h p.i. with SARS-CoV-2 ( n = P5, A5, O5). Bin size is 50 bases. Colour blocks indicate the start coordinates of annotated viral genes. e , Number of genomic mutations occurring <16 kb in genome, shown by age group. Data generated from n = P5, A5, O5. f , Hypothesis of SARS-CoV-2-infected goblet 2 PLAU+ cells becoming protective goblet 2 inflammatory cells through increased interferon and defective viral genome production. Drawn using Biorender.com . g , Transmission electron micrographs of goblet cells at 72 h p.i. with SARS-CoV-2 at different magnifications. Scale bar, 2 μm. Viral particles are false-coloured in red and indicated with white arrows. Lines in box and whisker plots ( b , e ) indicate median, IQR and minimum to maximum of the distribution, with individual values for each cell ( b ) or NEC culture ( e ) shown.

Infected older adult cultures express pro-fibrotic and EMT markers

As discussed above, SARS-CoV-2 infection in older adult cultures led to an increase in basaloid-like 2 cells (Fig. 5a ) associated with a pro-fibrotic state and epithelial–mesenchymal transition (EMT), including expression of ITGB6 , VIM and KRT5 (Fig. 5b and Extended Data Fig. 1d ). Typically membrane bound proteins such as ITGB6, ITGAV and TMPRSS2, produced by these cells, were more abundant in the supernatant of infected cultures from older adults (Fig. 5c and Extended Data Fig. 9a ), possibly originating from shed cells or debris. Vimentin (VIM) was upregulated in cell lysates of SARS-CoV-2-infected older adult cultures compared with mock ( n = 9; P < 0.05) (Fig. 5d and Extended Data Fig. 9b ). Immunofluorescence microscopy revealed the co-localization of ITGB6 protein with SARS-CoV-2 S protein (Fig. 5e and Extended Data Fig. 9c,d ) and the formation of vimentin cages around the virus in some infected older adult cells (Fig. 5e and Extended Data Fig. 9e–g ) 26 . Rare instances of migrating basal cell types (defined by the presence of cytokeratin bundles) burdened with viral compartments were also observed, suggesting that KRT5+, ITGB6+ and VIM+ cells are permissive to SARS-CoV-2 infection (Fig. 5f and Extended Data Fig. 9h ).

a , Frequency of KRT5 hi basal airway epithelial cells in mock (black outline) and SARS-CoV-2-infected (red outline) conditions across all timepoints (4, 24 and 72 h p.i.) with respect to age. Data shown in ratio of cell numbers per 1,000 cells per age group within scRNA-seq dataset, where the colour of the bars indicates fold change (FC) from the matched cell compartment in the mock condition. b , UMAP visualization of expression of differentially expressed genes ( ITGB6 , KRT5 and Vimentin (VIM) ) in basaloid-like 2 cells. Gene expression is shown in log1p scale. c , Volcano plot of differentially expressed proteins in the apical secretome of mock- and SARS-CoV-2-infected cultures that were unique (highly expressed) in the older adult dataset. Blue highlights those that are highly expressed in mock compared with SARS-CoV-2 infection conditions and black are enriched with infection; of note: ITGAV, ITGB6 and TMPRSS2 in red. The red horizontal line signals statistical significance threshold (adjusted P values ≤0.05). Two vertical lines show the threshold of log 2 fold-change ≥0.5 and ≤−0.5. d , Analysis of vimentin protein levels by Western blot normalized to GAPDH ( n = P5, A9, O9), subjected to multiple paired ratio t -test. e , Representative immunofluorescence images of basaloid-like 2 cell markers in older adults at 72 h p.i. with SARS-CoV-2. Maximum intensity projection images of immunofluorescence staining in fixed older adult NECs. Left: cyan, ITGB6; white, KRT5; yellow, SARS-CoV-2 spike protein; and composite with F-actin (magenta, phalloidin) and DAPI (blue). Right: green, vimentin; F-actin (grey, phalloidin); red, SARS-CoV-2 S protein; and composite with DAPI (blue). White arrows annotate the vimentin cage structure around SARS-CoV-2 S protein. f , Transmission electron micrograph of migrating basal KRT5+ epithelial cell in older adult cultures at 72 h p.i. with SARS-CoV-2 (white arrow). Cytokeratin bundles are indicated (grey arrows) and viral compartments (VC) containing viral particles false-coloured in red. Scale bars, 5 μm (left) and 0.5 μm (right). g , Hypothesis that infection of older adult cells leads to increased shedding of cells heavily burdened with viral particles, which may result in further spread of infection. Repair processes increase KRT5+ and ITGB6+ basaloid-like 2 cells, which are prioritized over the early antiviral responses from goblet 2 inflammatory cells, thereby elevating viral titre. Drawn using Biorender.com .

Although basaloid-like 2 cells showed low levels of viral transcription (Fig. 1g ), the most severely infected and damaged cells are probably shed into the secretome (as hypothesized in Fig. 5h ), leading to more ITGB6 protein (Fig. 5c ) and protruding cells (precursors of shed cells) in infected older adult cultures (Fig. 2e ).

ITGB6 expression in repair enhances viral replication

To investigate the role of basaloid-like 2 cells in SARS-CoV-2 pathogenesis, we performed gene set enrichment analysis (GSEA) and found that these cells are associated with extracellular matrix reorganization, wound response and migration processes (Fig. 6a ). Such processes may facilitate viral spread, metastasis and fibrogenic remodelling 27 , 28 , 29 . They also showed upregulation of alternative viral entry receptors CTSL , FURIN , NRP1 and NRP2 (Extended Data Fig. 10a ), suggesting their potential as targets for infection and spread.

a , GSEA indicating enriched gene ontology terms for basaloid-like 2 cells obtained using ShinyGo. b , Schematic to show the different wound healing assay protocols. c , Representative immunofluorescence images of basaloid-like 2 cell markers at 24 h post-wound NECs. Top: maximum intensity projection images (left to right): F-actin (grey, phalloidin); yellow, vimentin; and composite with DAPI (blue). Bottom (left to right): white, KRT5; cyan, ITGB6; and composite with F-actin (magenta, phalloidin) and DAPI (blue). Scale bar, 200 µm. Basaloid-like 2 cell markers mean fluorescence signal around wound area. Wound area shown by dotted red outline. d – f , Analysis of maximal intensity projections of fixed NECs without (−) and with (+) wounds at 24 h post wounding. d , KRT5+ (mean) signal ( n = 9; P3, A3, O3). e , Vimentin+ (mean) signal ( n = 5; P2, A1, O2). f , ITGB6+ % coverage ( n = 10; P4, A4, O2), subjected to ratio paired t -test. Wound healing rate in NECs from different age groups with mock or SARS-CoV-2 infection. g , Percentage wound closure (healed) per hour (% h −1 ), subjected to two-way ANOVA with Sidak’s multiple comparisons test ( n = P8, A5, O4). h , The difference in wound closure per hour between mock and SARS-CoV-2-infected cells from the same donor. Mean ± s.d. ( n = P8, A5, O4), subjected to one-way ANOVA with Tukey’s multiple comparisons test. Age variable shown as shape (triangles, adults; circles, paediatric). i , dsRNA coverage for NECs irrespective of age group at 72 h p.i. Determined by percentage area covered with dsRNA signal (yellow) from maximum intensity projections of fixed NECs, subjected to ratio paired t -test ( n = 5; P2, A1, O2). j , Representative immunofluorescent images from 72 h p.i. NECs with SARS-CoV-2 without (top) and with (bottom) wounding stained for dsRNA (yellow). Percentage area covered (right) with dsRNA+ signal from maximum intensity projections of fixed NECs using threshold analysis (red) in ImageJ, with the percentage coverage given at the bottom right of each image. k , Representative immunofluorescence images of basaloid-like 2 cell markers ITGB6 (cyan), KRT5 (white), dsRNA (yellow) and F-actin (magenta, phalloidin) in SARS-CoV-2-infected NECs. Maximum intensity projection images from wounded cultures after 24 h, shown both as maximal projections (top) and as an orthogonal view (bottom). KRT5 (white) is omitted from composite images, so that overlap of ITGB6 (cyan) and dsRNA (yellow) is apparent (white). l , Infectious viral titres at 72 h p.i. in combined cell lysate and apical fluid of SARS-CoV-2 nasal epithelial cells from non-wounded (−) and wounded (+) donors that were previously shown to propagate low levels of infectious particles (<10,000 p.f.u. per donor at 72 h p.i.). Infectious viral load in combined apical and cell lysates (p.f.u. per donor) were determined by plaque assays, with representative plaque assay wells shown (bottom). Subjected to paired t -test ( n = 8; P6, A2).

To functionally observe these processes, we employed a wound healing assay (Fig. 6b ). This assay enabled us to stimulate epithelial repair pathways, resulting in the increased expression of basaloid-like 2 cell markers around the wound site including KRT5 protein (Fig. 6c,d and Extended Data Fig. 10b,c ) (mean signal ± s.d. 62.3 ± 8.40 to 94.3 ± 21.1; P < 0.001, n = 9), VIM (Fig. 6c,e and Extended Data Fig. 10d,e ) (mean signal ± s.d. 2,887 ± 1,378 to 14,088 ± 518; P < 0.002, n = 5) and ITGB6 (Fig. 6c,f and Extended Data Fig. 10f,g ) (%coverage ± s.d. 0.72 ± 0.05 to 8.13 ± 4.73; P < 0.001, n = 9). Although we found no difference in wound healing rate of uninfected cultures across ages (Extended Data Fig. 2c ), SARS-CoV-2-infected older adult cultures exhibited a faster ( P = 0.01) wound healing rate (% h −1 , mean ± s.d. 8.01 ± 2.67% n = 4) compared with infected paediatric cultures (3.67 ± 2.78%, n = 8) (Fig. 6g,h and Extended Data Fig. 10h ), indicating greater cell motility and altered repair processes in the older adult. Stimulating wound repair also correlated with an increase in SARS-CoV-2 infection, as evidenced by a higher percentage of dsRNA-positive cells (indicative of replicating virus) in wounded cultures (mean ± s.d. 4.09 ± 3.61% to 9.69 ± 9.04%; P = 0.03, n = 5) (Fig. 6i,j and Extended Data Fig. 10i ), particularly around the site of the wound (Fig. 6k and Supplementary Fig. 1 ). Finally, cultures initially generating low infectious particle counts (<10,000 p.f.u. per donor at 72 h p.i.) showed increased viral particle production upon wounding ( P = 0.006, n = 8) (Fig. 6l ). These data suggest that basaloid-like 2 cells play a role in viral spread and their involvement in the wound healing process may contribute to SARS-CoV-2 infection and replication.

In our comprehensive study of SARS-CoV-2 infection in human NECs, we identified age-associated differences in COVID-19 pathogenesis. Key findings include the induction of a strong early interferon response in paediatric epithelial cultures infected by SARS-CoV-2, leading to incomplete viral replication. In contrast, NEC cultures derived from older adults produce more infectious viruses across various epithelial cell types when compared with paediatric cultures. Moreover, infected NECs from older adults exhibit increased cell shedding, thinning and leakiness, accompanied by the migration of basaloid-like 2 cells associated with wound repair. Interestingly, we showed that previous wounding of cultures resulted in an increased expression of basaloid-like 2 cell genes, promoting viral spread and ultimately augmenting infectious viral yield. Together, these findings contribute towards a deeper understanding of the age-specific nuances of the upper airway and the effects these may have on the pathogenic mechanism underlying SARS-CoV-2 infection across different ages.

Our in vitro model using primary NECs closely resembles SARS-CoV-2 infection in the human airway, the primary site of infection 30 . It confirms age-related changes in upper airway progenitor basal cell types reported previously 10 , 31 and allows for the detection of intrinsic age-related differences in epithelial cells without confounding variations in host immunity.

Notably, we observed a significant shift in the SCGB1A1 hi cell population, transitioning from goblet cells in paediatric cultures to secretory cells with age, with the latter expressing higher levels of SARS-CoV-2 entry factors (ACE2 and TMPRSS2). In paediatric cultures, goblet 2 cell types were a primary target of infection, while in older adult cultures, infected secretory cells accounted for the highest proportion of viral reads.

Through the integration of existing in vivo COVID-19 datasets, we confirmed the existence of both basaloid-like 2 and goblet inflammatory cells identified in vitro to be induced in an age-dependent response to infection. This validates the early epithelial response to SARS-CoV-2 in our in vitro model. However, we acknowledge differences between the in vitro models and patient responses. For example, basaloid-like 2 cells are far less abundant in vivo, as has been reported 32 , which may be due to the site of sampling, cell dissociation protocols or other technical factors 33 . On the other hand, viral and cellular dynamics can be timed more precisely in vitro, while the time interval from the initial infection to sampling is largely unknown for in vivo studies as they are estimated from symptom onset.

We found that fewer paediatric cell types contained viral reads compared with adult and older adult cultures. This is consistent with previous studies indicating that infection in paediatric cells is confined to a limited number of cells due to an early interferon response that limits viral spread 34 . We suggest that this effect is attributed to goblet 2 inflammatory epithelial cells, which decrease with age. These cells have the highest viral genome burden and the strongest interferon signature of all epithelial subtypes. Interestingly, our data suggest incomplete viral replication, increased subgenomic RNA and fewer infectious viruses in paediatric cultures, indicating more defective viral genomes, presumably due to the strong interferon response. Similar observations have been made in animal challenge experiments 35 and patient studies 36 , 37 , in which discrepancies between viral RNA and infectious viral load were also reported.

SARS-CoV-2 infection in older adult NECs led to epithelial damage and early signs of repair through cell migration and basal NEC proliferation. This was not observed in younger cultures. We also detected increases in ITGAV, ITGB6 and VIM proteins, which were attributed to the emergence of basaloid-like 2 cells. ITGB6 is expressed exclusively on epithelial cells but is virtually absent or expressed at very low levels in normal healthy adult epithelium 15 . It is highly upregulated in response to injury 38 and is associated with fibrotic lung disease and epithelial cancers 17 , 39 .

Integrins also modulate cytokine expression and activate TGF-β1, implicated in fibrosis and EMT 38 , a process with distinct pathological roles in wound healing, tissue regeneration and organ fibrosis and cancer 40 . We hypothesize that age-dependent reprogramming of infected NECs contributes to COVID-19 pathogenesis by prolonging disease and enhancing viral spread.

SARS-CoV-2, influenza and other respiratory infections have previously been linked to dysregulated epithelial repair processes and disease pathogenesis 41 , 42 , 43 . We hypothesize that SARS-CoV-2 infection in older adult NECs leads to the emergence of the basaloid-like 2 cell type and drives EMT repair pathways. Elderly cultures infected with SARS-CoV-2 exhibit flattened epithelial tissue, decreased resistance and increased cell shedding, indicating EMT activation 44 . Such functional changes facilitate disease progression and potentially enhance viral spread 45 , 46 . Ultrastructural and immunofluorescence studies confirm significant SARS-CoV-2 infection in shed cells in severe COVID-19 cases 47 . Elevated vimentin levels, an EMT and basaloid cell marker, are also present in these cultures. Our immunofluorescent assays reveal unique vimentin cage-like structures known to recruit viral components for assembly and egress 26 . In addition, the virus may directly interact with ITGB6, a component of caveolae involved in viral internalization 38 , 48 , 49 . In vitro studies suggest that the SARS-CoV-2 spike protein interacts with integrins 50 , 51 , potentially serving as a viral entry route in non-ACE2-expressing cells, thereby promoting infection in older adults. These findings integrate into our proposed model, where older adult cultures are more prone to induce basaloid-like 2 cells in infection, and these cells support both viral spread and disease progression.

In summary, we have shown that SARS-CoV-2 shows age-specific tropism in nasal epithelial cells, targeting goblet cells in children and secretory cells in older adults. Paediatric cells exhibit a strong antiviral response, resulting in limited viral replication. Older adult cells undergo shedding and more epithelial damage. Altered repair pathways and an increase in basaloid-like 2 cells associated with fibrosis markers contribute to greater viral spread in older adults. These findings provide insights into age-related COVID-19 pathogenesis and demonstrate how impaired repair processes enhance SARS-CoV-2 infection in older individuals.

Participants and ethics

Participants were recruited from five large hospital sites in London, the United Kingdom: the Great Ormond Street Hospital NHS Foundation Trust, the University College London Hospitals NHS Foundation Trust, the Royal Free London NHS Foundation Trust (the Royal Free Hospital and the Barnet Hospital) and the Whittington Health NHS Trust from March 2020 to February 2021. All participants provided written informed consent. Ethics approval was given through the Living Airway Biobank, administered through the UCL Great Ormond Street Institute of Child Health (REC reference: 19/NW/0171, IRAS project ID: 261511, Northwest Liverpool East Research Ethics Committee). Exclusion criteria for the cohort included current smokers, active haematological malignancies or cancer, known immunodeficiencies, sepsis from any cause and blood transfusions within 4 weeks, known bronchial asthma, diabetes, hay fever and other known chronic respiratory diseases such as cystic fibrosis, interstitial lung disease and chronic obstructive pulmonary disease. Nasal brushings were obtained by trained clinicians from healthy paediatric (0–11 years), adult (30–50 years) and older adult (≥70 years) donors who tested negative for SARS-CoV-2 (within 24–48 h of sampling) and reported no respiratory symptoms in the preceding 7 weeks. Brushings were taken from the inferior nasal concha zone using cytological brushes (Scientific Laboratory Supplies, CYT1050). All methods were performed following the relevant guidelines and regulations. Details of the study population are shown in Supplementary Table 1 .

Differentiated human nasal epithelial cell culture

Human nasal brushings were collected fresh for this study and immediately placed in a 15 ml sterile Falcon tube containing 4 ml of transport medium (αMEM supplemented with 1× penicillin/streptomycin (Gibco, 15070), 10 ng ml −1 gentamicin (Gibco, 15710) and 250 ng ml −1 amphotericin B (ThermoFisher, 10746254)) on ice. Four matched paediatric nasal brush samples were sent directly for scRNA-seq 9 . To minimize sample variation, all samples were processed within 24 h of collection and cultured to P1 as previously described 52 . Briefly, biopsies were co-cultured with 3T3-J2 fibroblasts and Rho-associated protein kinase inhibitor (Y-27632) in epithelial cell expansion medium consisting of a 3:1 ratio DMEM:F12 (Gibco, 21765), 1× penicillin/streptomycin and 5% FBS (Gibco; 10270) supplemented with 5 μM Y-27632 (Cambridge Bioscience, Y1000), 25 ng ml −1 hydrocortisone (Sigma, H0888), 0.125 ng ml −1 EGF (Sino Biological, 10605), 5 μg ml −1 insulin (Sigma, I6634), 0.1 nM cholera toxin (Sigma, C8052), 250 ng ml −1 amphotericin B (Gibco, 10746254) and 10 μg ml −1 gentamicin (Gibco, 15710).

Basal cells were separated from the co-culture flasks by differential sensitivity to trypsin and seeded onto collagen I-coated, semi-permeable membrane supports (Transwell, 0.4 µm pore size, Corning). Cells were submerged for 24–48 h in an epithelial cell expansion medium, after which the apical medium was removed, and the basolateral medium was exchanged for epithelial cell differentiation medium to generate ‘air–liquid interface’ (ALI) conditions. PneumaCult ALI medium (STEMCELL Technologies, 05001) was used for differentiation media following manufacturer instructions. Basolateral media were exchanged in all cultures three times a week and maintained at 37 °C and 5% CO 2 . ALI cultures were maintained in PneumaCult ALI medium for 4 weeks to produce differentiated NECs for all downstream experimentation.

Wound healing assay

Mechanical injury of NEC cultures was performed by aspiration in direct contact with the apical cell layer using a P200 sterile pipette tip, creating a wound with a diameter ranging from 750 to 1,500 μm. After wounding, the apical surface of the culture was washed with 200 μl PBS to remove cellular debris. The area of the wound was tracked with the aid of time-lapse microscopy with images taken every 60 min at ×4 magnification (Promon, AIS v.4.6.0.5.). The wound area was calculated each hour using ImageJ. The initial wound area was expressed as 100% to account for variability of wound size. Wounds were considered to be closed when the calculated area fell below 2%, the effective limit of detection due to image processing. Wound closure was calculated as follows: Wound closure (%) = 100 − ((Area/Initial Area) × 100). Wound closure (%) plotted as a function of time (h) was used to calculate the rate of wound closure (% h −1 ).

Virus propagation

The SARS-CoV-2 isolate hCoV-19/England/2/2020 obtained from Public Health England (PHE) was used in this study. For virus propagation, the African green monkey kidney cell line Vero E6 (ATCC: CVCL_0574 ; a kind gift from The Francis Crick Institute, London, United Kingdom and authenticated for use in this study) was used. Vero E6 cells were maintained in DMEM supplemented with 5% FCS and 1× penicillin/streptomycin. Cell media were replenished three times a week and maintained at 37 °C and 5% CO2. Vero E6 cells were infected with an MOI of 0.01 p.f.u. per cell in serum-free DMEM supplemented with 1% NEAA, 0.3% (w/v) BSA and 1× penicillin/streptomycin. A mock condition was conducted in parallel in which an equivalent volume of PBS++ was used instead of viral inoculum. The viral and mock-inoculated cell media were collected after 48 h, centrifuged at 10,000 g for 10 min to remove cellular debris and stored at −70 °C. The viral titre was determined by plaque assay (see below).

Viral infection of NEC cultures

After 28 days, NEC cultures were rinsed with sterile PBS++ and then infected with viral inoculum suspended in PBS++ (4.5 × 10 4 p.f.u. ml −1 , ~0.1 MOI) or an equivalent volume of mock inoculum suspended in PBS++ (mock infection) for 1 h on the apical compartment at 37 °C and 5% CO 2 . The virus inocula were then removed, and the NEC cultures were washed with sterile PBS++ and incubated for up to 72 h. This timepoint was chosen as maximum viral replication was observed at days 2–3 in our pilot studies (Extended Data Fig. 3a ).

Infectious viral load quantification by plaque assay

Vero E6 cells were grown to confluence on 24-well plates and then inoculated with serial dilutions of apical supernatant and cell lysates from infected cultures for 1 h at 37 °C and 5% CO 2 . The inoculum was replaced by an overlay medium supplemented with 1.2% (w/v) cellulose and incubated for 48 h at 37 °C and 5% CO 2 . Plates were fixed with 4% (w/v) paraformaldehyde for 30 min and overlay was aspirated from individual wells. Crystal violet staining was performed for a minimum of 20 min, and then plates were washed with water. The number of visible plaques was counted.

Viral copy number quantification

Viral gene quantification was performed on apical wash supernatants from experiments. Samples were lysed in AVL buffer (Qiagen) and stored at −80 °C until further processing. Viral RNA extractions were performed using a QIAamp viral RNA kit (Qiagen) following manufacturer instructions. Extracted RNA samples (5 μl) were quantified in one-step RT–qPCR using AgPath-ID one-step RT–PCR (Applied Biosystems) with the following cycle conditions: 45 °C for 10 min, 95 °C for 15 min, (95 °C for 15 s + 58 °C for 30 s) in a total of 45 cycles.

Cellular gene quantification was performed with cultured cells collected at the end of the experiments. Cells were lysed in RLT buffer (Qiagen) and extraction was performed using an RNeasy mini kit (Qiagen) following manufacturer instructions. Total RNA was converted into cDNA with qScript cDNA supermix (Quantabio) following manufacturer instructions. RT–qPCR was performed using Taq Man Fast Advanced Master mix with the following cycle conditions: 50 °C for 2 min, 95 °C for 10 min, 95 °C for 30 s and 60 °C for 1 min in a total of 45 cycles. The expression was normalized with GAPDH and then presented as 2 −(ΔCт) in arbitrary units.

SARS-CoV-2 genomic sequencing

Viral genome read coverage.

To visualize the viral read coverage along the viral genome, we used the 10X Genomics cellranger barcoded binary alignment map (BAM) files for every sample. We filtered the BAM files to only retain reads mapping to the viral genome using the bedtools intersect tool 52 . We converted the BAM files into sequence alignment map (SAM) files to filter out cells that were removed in our single-cell data pre-processing pipeline. The sequencing depth for each base position was calculated using samtools count. To characterize read distribution along the viral genome, we counted transcripts of 10 different open reading frames (ORFs): ORF1ab, Surface glycoprotein (S), ORF3a, Envelope protein (O), Membrane glycoprotein (M), ORF6, ORF7a, ORF8, Nucleocapsid phosphoprotein (N) and ORF10.

Detection of SARS-CoV-2 subgenomic RNAs

Subgenomic RNA analysis was conducted using Periscope 53 . Briefly, Periscope distinguished sgRNA reads on the basis of the 5′ leader sequences being directly upstream from each gene’s transcription. The sgRNA counts were then normalized into a measure termed sgRPTL, by dividing the sgRNA reads by the mean depth of the gene of interest and multiplying by 1,000.

Mass spectrometry

Paired mock- and SARS-CoV-2-infected airway surface fluids from groups of 10 paediatric, adult and older adult cultures were selected for this assay. For mass spectrometry, samples were inactivated with the KeyPro UV LED decontamination system (Phoseon Technology) before removal from the Biosafety level 3 laboratory (BSL3). Proteins were precipitated using ice-cold acetone. Protein pellets were resuspended in the digestion buffer as previously described and trypsin (Promega) digested to peptides 54 . Peptides were desalted by solid phase extraction (SPE) and separated by reverse phase chromatography on a NanoAquity LC system coupled to a SYNAPT G2-Si mass spectrometer (Waters) in a UDMSE positive ion electrospray ionization mode. Raw MS data were processed using Progenesis QI analysis software (Nonlinear Dynamics). Peptide identification was performed using the UniProt human reference proteome, with one missed cleavage and 1% peptide false discovery rate (FDR). Fixed modifications were set to carbamidomethylation of cysteines and dynamic modifications of oxidation of methionine.

Western blot

Samples were resolved on 4–15% Mini-PROTEAN TGX Precast Protein Gel (Bio-rad, 4561083) with high molecular mass standards of 10–250 kDa. Proteins were transferred to a Trans-Blot Turbo Mini 0.2 µm nitrocellulose membrane in a Trans-Blot Turbo Transfer System (Bio-rad, 1704150). Membranes were blocked in Odyssey blocking buffer overnight at 4 °C. Membranes were probed with primary antibodies described in Supplementary Table 2 , with dilutions prepared in Odyssey blocking buffer. Incubation with primary antibodies was performed at room temperature (r.t.) for 1 h. These included rabbit anti-ACE2 recognizing both long and short isoforms (Abcam, ab15348, 1:2,000) and rabbit anti-ACE2 specific for the long isoform (Abcam, ab108252, 1:2,000), rat anti-alpha-tubulin (Sigma-Aldrich, MAB1864, 1:2,000) and acetylated forms (Sigma-Aldrich, T6793, 1:2,000), mouse anti-SARS-CoV-2 spike glycoprotein (Abcam, ab273433, 1:2,000), rabbit anti-GAPDH (Abcam, ab9485, 1:3,000), rabbit anti-vimentin (Abcam, ab16700, 1:500) and rabbit anti-E-cadherin (Abcam, ab40772, 1:10,000). After three 15 min washes in PBS containing 0.1% Tween 20, the membranes were incubated with the appropriate IRDye secondary antibodies: goat anti-mouse (LI-COR, 926-68070, dilution 1:18,000) and goat anti-rabbit (LI-COR, 926-32211, dilution 1:18,000), both at room temperature for 1 h. The blots were then visualized using an Odyssey CLx imager and quantified using Image Studio Lite software

Cytokine assay

Apical supernatants were collected by washing the apical surface with 200 μl of PBS. These were snap frozen at −70 °C and inactivated with the KeyPro UV LED decontamination system (Phoseon Technology) in the CL3 laboratory before handling them in a CL2 laboratory. Cytokine and chemokine levels were assessed in 25 μl of supernatants using the multiplex BD CBA bead-based immunoassay kits including: IL6: A7, 558276; IL8 (CXCL8): A9, 558277; TNFα: C4, 560112; IFNγ: E7, 558269; IP10 (CXCL10): B5, 558280; IFNα: B8, 560379; and IL10: B7, 558274. Data were acquired using the BD LSRII flow cytometer and concentrations were obtained from a standard curve (provided with the kit). Analysis was performed using the FCAP software (v.3.0, BD Biosciences).

Immunofluorescence confocal microscopy

For immunofluorescence confocal imaging, NEC cultures were fixed using 4% (v/v) paraformaldehyde for 30 min, permeabilized with 0.2% Triton X-100 (Sigma) for 15 min and blocked using 5% goat serum (Sigma) in PBS for 1 h. The cultures were then incubated overnight at 4 °C with primary antibodies described in Supplementary Table 2 , with dilutions prepared in 5% goat serum in PBS with 0.1% Triton X-100. The primary antibodies used included rabbit anti-ACE2 (Abcam, ab15348, diluted 1:200), mouse anti-MUC5AC (Sigma-Aldrich, MAB2011, diluted 1:500), rat anti-alpha-tubulin (tyrosinated) (Sigma-Aldrich, MAB1864, diluted 1:100), mouse anti-alpha-tubulin (acetylated) (Sigma-Aldrich, T6793, diluted 1:100), mouse anti-SARS-CoV-2 spike glycoprotein (Abcam, ab273433, diluted 1:500), rabbit anti-GAPDH (Abcam, ab9485, diluted 1:250), mouse anti-dsRNA (Jena Bioscience, RNT-SCI-10010500, diluted 1:100), rabbit anti-MX1 (Abcam, ab207414, diluted 1:250), rabbit anti-cytokeratin 5 conjugated with Alexa Fluor 647 (Abcam, ab193895, diluted 1:100), rabbit anti-vimentin (Abcam, ab16700, diluted 1:1,000), rabbit anti-IL28+29 (Abcam, ab191426, diluted 1:100), goat anti-BPIFA1 (Abcam, EB11482, diluted 1:100) and rat anti-integrin beta 6 (Abcam, ab97588, diluted 1:100).

Following primary antibody incubation, cultures were washed and then incubated with secondary antibodies diluted in 1.25% goat serum in PBS with 0.1% Triton X-100 at r.t. for 1 h the following day. The secondary antibodies included donkey anti-mouse Alexa Fluor 647 (Jackson ImmunoResearch, 715-605-151, 1:600), donkey anti-rat Alexa Fluor 647 (Jackson ImmunoResearch, 712-605-153, 1:600), donkey anti-mouse Alexa Fluor 594 (Jackson ImmunoResearch, 715-585-151, 1:600), donkey anti-rat Alexa Fluor 594 (Jackson ImmunoResearch, 712-585-153, 1:600), donkey anti-mouse Cy3 (Jackson ImmunoResearch, 715-165-151, 1:600), donkey anti-rabbit Cy3 (Jackson ImmunoResearch, 711-165-152, 1:600), donkey anti-rat Alexa Fluor 488 (Jackson ImmunoResearch, 712-545-153, 1:600), donkey anti-rabbit Alexa Fluor 488 (Jackson ImmunoResearch, 711-545-152, 1:600), donkey anti-mouse Alexa Fluor 488 (Jackson ImmunoResearch, 715-545-151, 1:600) and donkey anti-goat Alexa Fluor 488 (Jackson ImmunoResearch, 705-545-147, 1:600).

After the secondary antibody incubation, cultures were stained with Alexa Fluor 555 phalloidin (ThermoFisher, A34055 , 4 μg ml −1 ) for 1 h and DAPI (Sigma, 2 μg ml −1 ) for 15 min at r.t. to visualize F-actin and nuclei, respectively. Samples were washed three times with PBS containing 0.1% Tween 20 after each incubation step.

Imaging was carried out using an LSM710 Zeiss confocal microscope, and the resulting images were analysed using Fiji/ImageJ v.2.1.0/153c54 for metrics including mean intensity, cell protrusion, culture thickness, % signal coverage, wound area and pseudocolouring 55 . Intensity profiles were generated using Nikon NIS-Elements analysis module, and three-dimensional (3D) renderings of immunofluorescence images were produced with Imaris software (Bitplane, Oxford Instruments; v.9.5/9.6).

Transmission electron microscopy

Cultured NECs that were either SARS-CoV-2-infected or non-infected were fixed with 4% paraformaldehyde and 2.5% glutaraldehyde in 0.05 M sodium cacodylate buffer at pH 7.4 and placed at 4 °C for at least 24 h. The samples were incubated in 1% aqueous osmium tetroxide for 1 h at r.t. before subsequent en bloc staining in undiluted UA-Zero (Agar Scientific) for 30 min at r.t. The samples were dehydrated using increasing concentrations of ethanol (50, 70, 90, 100%), followed by propylene oxide and a mixture of propylene oxide and araldite resin (1:1). The samples were embedded in araldite and left at 60 °C for 48 h. Ultrathin sections were acquired using a Reichert Ultracut E ultramicrotome and stained using Reynold’s lead citrate for 10 min at r.t. Images were taken on a JEOL 1400Plus TEM equipped with an Advanced Microscopy Technologies (AMT) XR16 charge-coupled device (CCD) camera and using the AMT Capture Engine software.

Sample preparation for single-cell RNA sequencing

Cultured NECs were processed using an adapted cold-active protease single-cell dissociation protocol 56 , as described below, based on a previously used protocol 9 to allow for a better comparison of matched samples included in both studies. In total, NECs derived from n = 3 paediatric, 4 adult and 4 older adult donors were processed at 24, 48 and 72 h post infection (SARS-CoV-2 and mock) for scRNA-seq.

First, the transwell inserts, in which the NEC cultures were grown, were carefully transferred into a new 50 ml Falcon tube and any residual transport medium was carefully removed so as not to disturb the cell layer. Dissociation buffer (2 ml) was then added to each well, ensuring the cells were covered; 10 mg ml −1 protease from Bacillus licheniformis (Sigma-Aldrich, P5380) and 0.5 mM EDTA in HypoThermosol (STEMCELL Technologies, 07935). The cells were incubated on ice for 1 h. Every 5 min, cells were gently triturated using a sterile blunt needle, decreasing from a 21G to a 23G needle. Following dissociation, protease was inactivated by adding 400 µl of inactivation buffer (HBSS containing 2% BSA) and the cell suspension was transferred to a new 15 ml Falcon tube. The suspension was centrifuged at 400 g for 5 min at 4 °C and the supernatant was discarded. Cells were resuspended in 1 ml dithiothreitol wash (10 mM dithiothreitol in PBS) (ThermoFisher, R0861) and gently mixed until any remaining visible mucous appears to break down, or for ~2–4 min. The mixture was centrifuged at 400 g for 5 min at 4 °C and the supernatant was removed. The cells were resuspended in 1 ml of wash buffer (HBSS containing 1% BSA) and centrifuged once more under the same conditions. The single-cell suspension was then filtered through a 40 µm Flowmi cell strainer. Finally, the cells were centrifuged and resuspended in 30 µl of resuspension buffer (HBSS containing 0.05% BSA). Using trypan blue, total cell counts and viability were assessed. Cells (3,125) were then pooled together from the 4 biological replicates with corresponding conditions (for example, all mock viral treatments at 24 h) and the cell concentration was adjusted for 7,000 targeted cell recovery according to the 10x Chromium manual (between 700–1,000 cells per µl). The pools were then processed immediately for 10 × 5′ single-cell capture using the Chromium Next GEM Single Cell V(D)J reagent kit v.1.1 (Rev E Guide) or the Chromium Next GEM Single Cell 5′ V2 (Dual index) kit (Rev A guide). Each pool was run twice.

Of note, each sample was processed fresh for 5’ Next Gen single-cell RNA sequencing and thus pooled per timepoint when loading on the 10X chromium controller. Extra steps were taken where possible to balance sex, age as well as technical factors (that is, 10X chromium kit versions) within these sample pools. Furthermore, the downstream process of the sample pools, including library preparation and sequencing (see below) contained samples from the 4 h, 24 h and 72 h timepoints to mitigate additional technical effects. Timepoints can be seen to be well mixed within the single-cell dataset as visualized via a uniform manifold approximation and projection (UMAP) in Extended Data Fig. 1b .

For several samples (Supplementary Table 3 ), 1 µl viral RT oligo (either at 5 µM or 100 µM, PAGE) was spiked into the master mix (at step 1.2.b in the 10X guide, giving a final volume of 75 µl) to help with the detection of SARS-CoV-2 viral reads. The samples were then processed according to manufacturer instructions, with the viral cDNA separated from the gene expression libraries (GEX) by size selection during step 3.2. Here the supernatant was collected (159 µl) and transferred to a new PCR tube and incubated with 70 µl of SPRI beads (0.6× selection) at r.t. for 5 min. The SPRI beads were then washed according to the guide and the viral cDNA was eluted using 30 µl of EB buffer. Neither changes to the transcriptome were previously observed upon testing the addition of viral oligo 9 , nor were any significant changes observed with an increasing concentration upon comparison, outside of a small increase in the overall number of SARS-CoV-2 reads detected. The RT oligo sequence was as follows: 5′-AAGCAGTGGTATCAACGCAGAGTACTTACTCGTGTCCTGTCAACG-3′

Library generation and sequencing

The Chromium Next GEM Single Cell 5′ V2 kit (v.2.0 chemistry) was used for single-cell RNA-seq library construction. For all NEC culture samples, libraries were prepared according to manufacturer protocol (10X Genomics) using individual Chromium i7 sample indices. GEX libraries were pooled and sequenced on a NovaSeq 6000 S4 flow cell (paired-end, 150 bp reads), aiming for a minimum of 50,000 paired-end reads per cell for GEX libraries.

Single-cell RNA-seq data processing

Computational pipelines, processing and analysis.

The single-cell data were mapped to a GRCh38 ENSEMBL 93 derived reference, concatenated with 21 viral genomes (featuring SARS-CoV-2), of which the NCBI reference sequence IDs are: NC_007605.1 (EBV1), NC_009334.1 (EBV2), AF156963 (ERVWE1), AY101582 (ERVWE1), AY101583 (ERVWE1), AY101584 (ERVWE1), AY101585 (ERVWE1), AF072498 (HERV-W), AF127228 (HERV-W), AF127229 (HERV-W), AF331500 (HERV-W), NC_001664.4 (HHV-6A), NC_000898.1 (HHV-6B), NC_001806.2 (herpes simplex virus 1), NC_001798.2 (herpes simplex virus 2), NC_001498.1 (measles morbillivirus), NC_002200.1 (mumps rubulavirus), NC_001545.2 (rubella), NC_001348.1 (varicella zoster virus), NC_006273.2 (cytomegalovirus) and NC_045512.2 (SARS-CoV-2). When examining viral load per cell type, we first removed ambient RNA by SoupX 57 . The alignment, quantification and preliminary cell calling of NEC culture samples were performed using the STARsolo functionality of STAR v.2.7.3a, with the cell calling subsequently refined using the Cell Ranger v.3.0.2 version of EmptyDrops 58 . Initial doublets were called on a per-sample basis by computing Scrublet scores 59 for each cell, propagating them through an over-clustered manifold by replacing individual scores with per-cluster medians and identifying statistically significant values from the resulting distribution, replicating previous approaches 60 , 61 .

Quality control, normalization and clustering

Mixed genotype samples were demultiplexed using Souporcell 62 and reference genotypes. DNA from samples was extracted following manufacturer protocol (Qiagen, DNeasy blood and tissue kit 69504 and Qiagen Genomic DNA miniprep kit) and single nucleotide polymorphism (SNP) array-derived genotypes generated by Affymetrix UK Biobank Axiom Array kit by Cambridge Genomic Services (CGS). Cells that were identified as heterotypic doublets by Souporcell were discarded. Quality control was performed on SoupX-cleaned expression matrixes. Genes with fewer than 3 counts and cells with more than 30% mitochondrial reads were filtered out. Cells with a scrublet score >0.3 and adjusted P value < 0.8 were predicted as doublets and filtered out. Expression values were then normalized to a sum of 1 × 10 4 per cell and log-transformed with an added pseudocount of 1. Highly variable genes were selected using the scanpy.pp.highly_variable_genes() function in Scanpy. Principal component analysis (PCA) was performed and the top 30 principal components were selected as input for l. We performed graph-based batch integration with the bbknn method 63 using experimental pools and chemistry as batch covariate (encoded as ‘bbknn_batch’ in the object). Clustering was performed with the Leiden 64 algorithm on a k -nearest-neighbour graph of a PCA space derived from a log(counts per million/100 + 1) representation of highly variable genes, according to the Scanpy protocol 65 . Leiden clustering with a resolution of 1 was used to separate broad cell types (basal, goblet, secretory). For each broad cell type, clustering was then repeated, starting from highly variable gene discovery to achieve a higher resolution and a more accurate separation of refined cell types. Annotation was first performed automatically using a Celltypist 66 model built on the in vivo dataset of nasal airway brushes 9 , and then using manual inspection of each of the clusters and further manual annotation using known airway epithelial marker genes.

Developmental trajectory inference

Pseudotime inference was performed on the whole object or the basal/goblet compartment using Monocle 3 (refs. 67 , 68 ). Briefly, a cycling basal cell was chosen as a ‘root’ cell for the basal compartment, showing the highest combined expression of KRT5 , MKI67 and NUSAP1 genes. For the goblet compartment, a goblet 1 cell was chosen as a root, showing the highest combined expression of TFF3 , SERPINB3 , MUC5AC , MUC5B and AQP5 . Cells were grouped into different clusters using the group_cells() function, learning the principal graph using the learnGraph() function and ordering cells along the trajectory using the ordercells() function. A second pseudotime was inferred with Palantir (1.0.1) 69 . The cycling basal ‘root’ cell was determined as above and an unsupervised pseudotime inference was performed on a Scanpy-derived diffusion map. The five inferred endpoints were inspected and three were deemed to be very closely biologically related and replaced with a joint endpoint with the highest combined expression of OMG , PIFO and FOXJ1 . The pseudotime inference was repeated with the two remaining inferred endpoints and the marker derived one serving as the three terminal states.

Differential abundance analysis

To determine cell states that are enriched in the SARS-CoV-2 versus mock conditions for the different age groups, we used the Milo framework for differential abundance analysis using cell neighbourhoods 14 . Briefly, we computed k -nearest-neighbour graphs of cells in the whole dataset using the buildGraph() function, assigned cells to neighbourhoods using the makeNhoods() function and counted the number of cells belonging to each sample using the countCells() function. Each neighbourhood was assigned the original cluster labels using majority voting. To test for enrichment of cells in the SARS-CoV-2 condition versus the mock condition, we modelled the cell count in neighbourhoods as a negative binomial generalized linear model, using a log-linear model to model the effects of age and treatment on cell counts (logFC). We control for multiple testing using the weighted Benjamini–Hochberg correction as described in ref. 14 (spatialFDR correction). Neighbourhoods were considered enriched in SARS-CoV-2 vs mock if the spatialFDR < 0.1 and logFC > 0.

Expression signature analysis

To determine the enrichment of basaloid or interferon genes in the annotated clusters, we used the Scanpy function scanpy.tl.score_genes() to score the gene signature for each cell. The gene list for computing the basaloid score was composed of the EPCAM, CDH1, VIM, FN1, COL1A1, CDH2, TNC, VCAN, PCP4, CUX2, SPINK1, PRSS2, CPA6, CTSE, MMP7, MDK, GDF15, PTGS2, SLCO2A1, EPHB2, ITGB8, ITGAV, ITGB6, TGFB1, KCNN4, KCNQ5, KCNS3, CDKN1A, CDKN2A, CDKN2B, CCND1, CCND2, MDM2, HMGA2, PTCHD4 and OCIAD2 genes. The gene list for computing the IFN alpha score was composed of the ADAR, AXL, BST2, EIF2AK2, GAS6, GATA3, IFIT2, IFIT3, IFITM1, IFITM2, IFITM3, IFNAR1, IFNAR2, KLHL20, LAMP3, MX2, PDE12, PYHIN1, RO60, STAR and TPR genes and the gene list for computing the IFN gamma score was composed of the OAS3, OASL, OTOP1, PARP14, PARP9, PDE12, PIAS1, PML, PPARG, PRKCD, PTAFR, PTPN2, RAB20, RAB43, RAB7B, RPL13A, RPS6KB1, SHFL, SIRPA, SLC11A1, SLC26A6, SLC30A8, SNCA, SOCS1, SOCS3, SP100, STAR, STAT1, STX4, STX8, STXBP1, STXBP3, STXBP4, SUMO1, SYNCRIP, TDGF1, TLR2, TLR3, TLR4, TP53, TRIM21, TRIM22, TRIM25, TRIM26, TRIM31, TRIM34, TRIM38, TRIM5, TRIM62, TRIM68, TRIM8, TXK, UBD, VAMP3, VCAM1, VIM, VPS26B, WAS, WNT5A, XCL1, XCL2, ZYX genes, as used in ref. 9 .

Gene set enrichment analysis

Wilcoxon rank-sum test was performed to determine differentially expressed genes between clusters using the scanpy.tl.rank_genes_groups() function. Differentially expressed genes were further analysed using GSEA via ShinyGO 70 .

In vivo sub-analysis

Sex- and age-matched healthy adults and paediatric airway samples ( n = 10 total) were subsetted from our previous dataset 9 for label transfer of the in vitro cell annotation using CellTypist as described above. Selected sample IDs from the in vivo dataset are shown in Supplementary Table 4 . These were selected to match the mean age and range, and sex of the current study as the sample collection and processing were conducted in parallel between studies.

In vivo integration

We performed integration of 8 single-cell datasets comprising 614,695 cells from upper and lower airways from healthy and COVID-19 patients from paediatric (0–18 years), adult (19–50 years) and older adult (51–90 years) samples 9 , 10 , 12 , 18 , 19 , 20 , 21 , 22 . Expression values were then normalized to a sum of 1 × 10 4 per cell and log-transformed with an added pseudocount of 1. Highly variable genes were selected using the Scanpy function scanpy.pp.highly_variable_genes(). PCA was performed and the top 30 principal components were selected as input for Harmony 71 to correct for batch effects between studies and compute a batch-corrected k -nearest-neighbour graph. The clustering was performed with the Leiden 64 algorithm on a k -nearest-neighbour graph of a PCA space derived from a log(counts per million/100 + 1) representation of highly variable genes, according to the Scanpy protocol 65 . Leiden clustering with a resolution of 1 was used to separate broad cell types (basal, goblet, secretory) and subclustering was used for more accurate separation of fine-grained cell types. Annotation was first performed automatically using a Celltypist 66 model built on the in vivo dataset of nasal airway brushes 9 , and then using manual inspection of each of the clusters and further manual annotation using known epithelial marker genes.

Statistical analysis on in vivo dataset

Due to the large proportions of zero counts, we fitted zero-inflated Poisson (ZIP) models to the counts of nasal epithelial cells including the natural logarithm of the total number of cells per donor as an offset in the models for both basaloid and gobletInFam cells. This allowed us to estimate both the incidence of nasal epithelial cells () and the probability of a donor being in the zero counts class () as functions of disease and age groups. We first included interaction terms between the disease and age groups in both the incidence and the zero counts parts of the models. Generalized additive models for location, scale and shape were fitted using the packages gamlss 72 and glmmTMB 73 (to include random effects on the probability of zero class by donor), both in the R language and environment for statistical computing (v.4.2.3) 74 . Using the Bayesian Information Criterion (BIC) as a goodness-of-fit statistic, we decided to include the main effects of disease in both the linear predictors for incidence and probability of belonging to the zero class after stratifying by age group.

Statistical analysis

Statistical analysis was performed using R or GraphPad Prism 9 and details of statistical tests used are indicated. Data distribution was assumed to be normal unless stated differently, and a Kruskal–Wallis test was used to test for normality using R. The determination of sample sizes was guided by those established in previous scRNA-seq and studies using ALI cultures 9 , 75 , rather than through the application of specific statistical methods. In total, NEC cultures generated from 11 participants were used to create our in vitro single-cell dataset, including 3 paediatric (<12 years), 4 adult (30–50 years) and 4 older adult (>70 years) donors. Additional statistical power here was provided by the experimental design, sampling from multiple timepoints (4, 24 and 72 h post SARS-CoV-2 infection), with the inclusion of matched mock-infected controls for each. Samples were also carefully pooled (see Methods) to help avoid batch effects and run across multiple lanes on the 10X controller. Together, this resulted in a total of 66 NEC samples processed for single-cell sequencing, with a total of 139,598 high-quality cells sequenced. Further validation of our in vitro single-cell data and our key observation was provided using an integrated in vivo single-cell dataset (using published patient datasets) and numerous experimental validation assays. Data collection and analysis were not performed blind to the conditions of the experiments. Representative images are displayed as examples for quantified data (1 n of the total n noted in their corresponding summary graphs) unless otherwise stated in the figure legend.

Reporting summary

Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article.

Data availability

RNA-seq data are available in the European Genome-Phenome Archive (EGA) ( https://ega-archive.org/ ) under accession number EGAD00001015345 . The datasets from our study can be downloaded and explored interactively through a web portal ( https://covid19cellatlas.org , https://www.covid19cellatlas.org/ALI_COVID19/in-vitro/ , https://www.covid19cellatlas.org/ALI_COVID19/in-vivo/ ). Quality control metrics for our single-cell data are provided on the web portal page. All other data needed to evaluate the conclusions are available within the Article or its Supplementary Information . Viral sequences resulting from this study can be found on Genbank under the accession numbers PP346398 – PP346416 . Source image files for the main figures are available via Figshare at https://doi.org/10.6084/m9.figshare.25193618.v1 (ref. 76 ). Source image files for the extended figures are available via Figshare at https://doi.org/10.6084/m9.figshare.25194005.v1 (ref. 77 ). Source image files for supplementary data are available via Figshare at https://doi.org/10.6084/m9.figshare.25196396.v1 (ref. 78 ). Source data are provided with this paper.

Code availability

Custom code for the analysis performed in this study is publicly available via GitHub at https://github.com/Teichlab/ALI_COVID19 (ref. 79 ). Free data access to the single-cell objects used in this study is available at https://www.covid19cellatlas.org/ .

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Acknowledgements

This work was funded by a UKRI/BBSRC research grant (BB/V006738/1 awarded to C.M.S., M.Z.N., S.A.T., W.B., C.O., C.R.B., R.E.H.) and the NIHR Great Ormond Street Hospital Biomedical Research Centre. The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. We acknowledge funding from Wellcome (WT211276/Z/18/Z and Sanger core grant WT206194 to S.A.T.). M.Z.N. and K.B.M. were funded by the Rosetrees Trust (M944) and Action Medical Research (GN2911). The project received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement 874656. M.Z.N. acknowledges funding from an MRC Clinician Scientist Fellowship (MR/W00111X/1) and the Rutherford Fund Fellowship allocated by the MRC UK Regenerative Medicine Platform 2 (MR/5005579/1). This project was made possible in part by grants 2017-174169 and 2019-202654 from the Chan Zuckerberg Foundation. C.M.S. was supported by grants from Animal Free Research UK (AFR19-20274), GOSH Children’s Charity (COVID_CSmith_017) and the Wellcome Trust (212516/Z/18/Z). Microscopy was performed at the Light Microscopy Core Facility, UCL GOS Institute of Child Health supported by the NIHR GOSH BRC award 17DD08. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health. We acknowledge D. Sumanaweera (Wellcome Sanger Institute) for advice on some of the bioinformatic analysis and A. Ma (UCL GOS Institute of Child Health) for help with the analysis of NEC culture heights; Sanger IT and CellGenIT for help; Public Health England for providing the SARS-CoV-2 (hCoV-19/England/2/2020); and the Cell Services science technology platform (STP) at the Francis Crick Institute, London, UK for providing the African green monkey kidney cell line Vero E6 (ATCC: CVCL_0574 authenticated for use in this study).

Author information

These authors contributed equally: Maximillian Woodall, Ana-Maria Cujba, Kaylee B. Worlock.

These authors jointly supervised this work: Sarah A. Teichmann, Kerstin B. Meyer, Marko Z. Nikolić, Claire M. Smith.

Authors and Affiliations

Great Ormond Street UCL Institute of Child Health, London, UK

Maximillian N. J. Woodall, Katie-Marie Case, Tereza Masonou, Samuel Ellis, Machaela Palor, Dale Moulding, Chris O’Callaghan, Paolo DeCoppi, Mario Cortina-Borja, Heloise Vinette, Sunando Roy, Judith Breuer, Wendy E. Heywood, Kevin Mills & Claire M. Smith

Wellcome Sanger Institute, Cambridge, UK

Ana-Maria Cujba, Krzysztof Polanski, Ni Huang, Rik G. H. Lindeboom, Lira Mamanova, Liam Bolt, Laura Richardson, Batuhan Cakir, Sarah A. Teichmann & Kerstin B. Meyer

UCL Respiratory, Division of Medicine, University College London, London, UK

Kaylee B. Worlock, Masahiro Yoshida, Eliz Kilich, Puja Mehta, Rachel C. Chambers & Marko Z. Nikolić

UCL Institute of Ophthalmology, University College London, London, UK

Thomas Burgoyne

Royal Brompton Hospital, Guy’s and St Thomas’ NHS Foundation Trust, London, UK

Thomas Burgoyne & Andreia Pinto

UCL Centre for Clinical Microbiology, Division of Infection and Immunity, University College London, London, UK

Timothy D. McHugh

Royal Free Hospital NHS Foundation Trust, London, UK

Aarash Saleh

University College London Hospitals NHS Foundation Trust, London, UK

Eliz Kilich, Puja Mehta & Marko Z. Nikolić

Department of Infectious Disease, Imperial College London, London, UK

Jie Zhou & Wendy Barclay

Great Ormond Street Hospital NHS Foundation Trust, London, UK

Paolo DeCoppi & Colin R. Butler

Epithelial Cell Biology in ENT Research (EpiCENTR) Group, Developmental Biology and Cancer Department, Great Ormond Street UCL Institute of Child Health, University College London, London, UK

Colin R. Butler & Robert E. Hynds

UCL Cancer Institute, University College London, London, UK

Robert E. Hynds

Theory of Condensed Matter, Cavendish Laboratory/Dept Physics, University of Cambridge, Cambridge, UK

Sarah A. Teichmann

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Contributions

M.N.J.W., A.-M.C., K.B.W., M.Y. and K.-M.C. designed the study, conducted experiments, analysed data and reviewed the manuscript. K.B.W. and M.Y. performed 10x and isolated DNA for genotyping. K.P., N.H. and R.G.H.L. assisted with computational analysis, including providing code for viral distribution analysis and customized dotplot functions. A.S., E.K., P.M., C.O., C.R.B., P.D.C. and M.Z.N. recruited patients and collected nasal brushings and clinical metadata. L.M., L.B. and L.R. prepared sequencing libraries and conducted the sequencing. A.P. and T.B. assisted with transmission electron microscopy image analysis and review of the manuscript. M.P. assisted with cell culture. S.E. assisted with the analysis of the TEM images and the addition of pseudocolour. T.M. assisted with flow cytometric bead assays and scRNA-seq data analysis and review of the manuscript. S.R. and J.B. assisted with viral genomic data analysis and review of the manuscript. W.E.H., H.V. and K.M. assisted with mass spectrometry data analysis and review of the manuscript. D.M. assisted with microscopy data acquisition and reviewed the manuscript. C.M.S., C.O., P.D.C. and C.R.B. provided support through ethics and patient recruitment. M.C.-B. provided statistical support. S.R. and J.B. oversaw viral genomics analysis and interpretation and review of the manuscript. J.Z. and W.B. facilitated the collection of preliminary data. T.D.M. provided support in setting up and training for all BSL3 work. B.C. facilitated data upload on COVID-19 portals. M.N.J.W., A.-M.C., K.B.W., K.B.M., M.Z.N. and C.M.S. wrote the manuscript. P.D.C., C.O., W.B., S.A.T., K.B.M., C.R.B., R.E.H., M.Z.N. and C.M.S. conceived and designed the study, oversaw the funding application and reviewed the manuscript. S.A.T., R.C.C., K.B.M, R.E.H, M.Z.N. and C.M.S. oversaw data analysis and interpretation, and the write-up of the manuscript.

Corresponding authors

Correspondence to Sarah A. Teichmann , Kerstin B. Meyer , Marko Z. Nikolić or Claire M. Smith .

Ethics declarations

Competing interests.

In the past three years, S.A.T. has received remuneration for Scientific Advisory Board Membership from Sanofi, GlaxoSmithKline, Foresite Labs and Qiagen. S.A.T. is a co-founder and holds equity in Transition Bio and Ensocell. Starting 8 January 2024, S.A.T. has been a part-time employee of GlaxoSmithKline. All other authors declare no competing interests.

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Peer review information.

Nature Microbiology thanks Ivan Zanoni and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Extended data

Extended data fig. 1 paediatric nasal epithelial cells have less basal cell subtypes compared to adult and older adult nasal epithelial cells but display comparable differentiation markers and sars-cov-2 entry factor expression..

(a) Violin plot visualization of threshold for percentage of mitochondrial reads in scRNAseq dataset. (b) Uniform manifold approximation and projection (UMAP) visualizations showing good integration of donor IDs, donor pool, treatment, age group, time after infection, 10X Chromium kit version, sex, cell cycle phase and introduced spike-in primer after batch correction (see Methods for more details). (c) Boxplot indicating comparison of cell cycle phase states (G1, G2M, S) amongst the three age groups in mock/infected/combined (All) conditions. (d) Dot plot visualization showing marker genes for annotated airway epithelial cell types, with fraction of expressing cells and average expression within each cell type indicated by dot size and colour, respectively. Broad cell domains are colour coded; KRT5 hi (purple), SCGB1A1 hi (green) and ciliated/other (yellow). Logistic regression based label transfer using Celltypist for the data sets in (e) Yoshida et al. 9 and (f) Ziegler et al. 12 , with fraction of matched cells and average probability score indicated by dot size and colour, respectively (g) Numbers of annotated airway epithelial cells in respect to age (data shown in ratio of cell numbers/per 1000 cells in age dataset). (h) Representative maximum intensity z-projections of confocal images (left and central) and transmission electron micrographs (right panels) of NEC cultures differentiated at an air–liquid interface and immunolabeled against cilia (tubulin, green) and mucin (MUC5AC, red), with DAPI (blue) and phalloidin (grey) to indicate the nucleus and actin filaments, respectively. Scale bar 10-μm applies to all images in the row.

Extended Data Fig. 2 Physiological differences in paediatric, adult and older adult nasal epithelial NEC cultures.

Physiological comparison of paediatric (P), adult (A) and older adult (O) NEC cultures as measure by; (a) ciliary beat frequency (CBF)(Hz) (n = P6, A6, O7); (b) the percentage of +ve ɑ-tubulin staining coverage per 225 μm2 section (n = P6, A4, O5); (c) motility measured by percentage scratch closure over time (n = P8, A3, O8) and (d) culture thickness (n = P9, A5, O7). For ( a-d ) data was plotted as mean ± SD, subject to one-way ANOVA with Tukey’s multiple comparison test (e) Representative light microscope images of whole well scans of NEC cultures depicting the characteristic differences in culture morphology with age (P=Paed, A=Adult, E=Older adult). (f) Comparison of epithelial integrity via trans-epithelial electrical resistance (TEER) (Ω.cm 2 ). Mean ± SD (n = P12, A8, O8) plotted across the age groups using one-way ANOVA with Tukey’s correction. (g) Alternate SARS-CoV-2 entry factor gene expression per cell type calculated based upon absolute cell numbers with the average expression of BSG, CTSL, NRP1, NRP2 and FURIN indicated by colour. Dot size corresponds to the total number of cells expressing alternate viral entry genes in respective age groups in the mock condition. ( h ) Palantir inferred probabilities of cycling basal cells differentiating into basaloid-like 2 or goblet 2 inflammatory cells. (i) Boxplot showing the distribution of pseudotime within each cluster among goblet cell subtypes. (j) Palantir inferred probabilities of cycling basal cells differentiating into basaloid-like 2 cells. (k) Boxplot showing the distribution of pseudotime within each cluster among KRT5 hi cell subtypes. Lines in box and whisker plots i, j indicates median, interquartile range, and minimum to maximum of the distribution, with individual values for each cell shown.

Extended Data Fig. 3 Elderly cells replicate more infectious viruses with a greater distribution of viral reads across epithelial subtypes.

(a) Mean viral replication shown as pfu/ml per donor over a 5-day period (n = 35: P15, A10, O10). (b) Exemplar image of plaque assay used to determine infectious viral load. (c) UMAP of airway cells with detected SARS-CoV2 mRNA in each cell type in cultures mock and SARS-CoV-2 infected for all time points and ages combined (≥1 viral UMI per donor following filtering out ambient RNA). (d) Pie charts showing the fractions of annotated airway epithelial cells containing viral reads at 4 h, 24 h and 72 h p.i. in respect to age. (e) Numbers of annotated airway epithelial cells containing viral reads at 24 h and 72 h post infection (red) in respect to age with total number of cells in each subset (grey) (data shown as cell numbers/per 1000 cells in age dataset). (f) Representative orthogonal views of z-stacks from fixed paediatric (top), adult (middle) and older adult (bottom) NECs at 72 h p.i. with SARS-CoV-2. Sections were immunolabeled against F-actin (phalloidin, grey) DAPI (blue) and SARS-CoV-2 S protein (red). The scale bar represents 10 μm. (g) Linear regression analysis of viral reads vs ACE2 and TMPRSS2 expression per cell at 72 h post infection. Data represents all age groups combined (h) Linear regression analysis of viral reads vs ACE2 and TMPRSS2 expression per cell and grouped by cell domains (i) Linear regression of infectious viral titres in combined cell lysate and apical fluid of SARS-CoV-2 nasal epithelial cells from donors of different ages as determined by plaque assays (n = 29). Subject to Pearson correlation with SE shown for line error.

Extended Data Fig. 4 Minimal cytopathology following SARS-CoV-2 infection of NECs.

(a) Orthogonal views of the z-stacks showing the thickness and morphology from fixed paediatric, adult and older adult NECs from 3 separate donors at 72 h p.i. mock or SARS-CoV-2 infected NEC cultures. Sections were immunolabeled against cilia (tubulin, cyan), F-actin (phalloidin, magenta) DAPI (blue), SARS-CoV-2 S protein (yellow) and cytokeratin 5 (KRT5+, white). Scale bar = 50 µm. (b) Representative maximal intensity projections (top panels) and orthogonal z sections (bottom panels) of NECs stained for E-Cadherin at 72 h p.i. with mock or SARS-CoV-2 (scale bar 50 μm) and expression determined via Western blots and normalised to GAPDH. Data plotted as mean ± SD, subject to one-way ANOVA with Tukey’s multiple comparison test, with individual values shown (n = P5, A5, O5). (c) Representative orthogonal views of the z-stacks showing the localisation of KRT5+ve cells (white) from example NEC cultures (summary in Fig. 2d ). KRT5+ve cells above the horizontal yellow line are classified as non-basal -layer (not in contact with basement membrane), F-actin (phalloidin, magenta) stain references apical membrane and tight-junctions. Each section is 225 µm in width. (d) Maximal projections of the z-stacks showing the localisation of KRT5+ve cells (white) from above and below the horizontal yellow line (classified as non-basal -layer) from example air–liquid interface cultures at 72 h p.i. with mock or SARS-CoV-2 (scale bar 50 μm). (e) Transmission electron micrograph of epithelial cell shedding (white arrows) at 72 h p.i. with SARS-CoV-2 (scale bar 10 μm).

Extended Data Fig. 5 Cytopathology and changes in cell types.

(a) Cilia coverage for each age group at 72 h p.i. Mock and SARS-CoV-2. (left) Representative Immunofluorescent images from 72 h p.i. NECs with mock and SARS-CoV-2 condition stained for a-tubulin (cyan) (scale bar = 50 µm). Percentage area covered (right) with αTubulin+ve signal (cyan) from maximum intensity projections of fixed NECs using threshold analysis (red) in ImageJ. Summary of cilia coverage (right) (n = P5, A4, O5). Subject to one-way ANOVA with Tukey’s multiple comparison test. For 72 h p.i. (mock and SARS-CoV-2 conditions) NECs were compared between age groups, looking at average (b) cilia beat frequency (Hz) (n = P8, A8, O8); (c) α-Tubulin protein expression (n = P11, A8, O7) and (d) SARS-CoV-2 entry factor protein expression (ACE2, TMPRSS2 and short ACE2). Protein levels were determined via Western blot and normalised to GAPDH (n = P6-8, A5-9, O5-8). Data for b-d plotted as mean ± SD, with individual values shown. (e) Total numbers of annotated airway epithelial cells in all mock infected vs all SARS-CoV-2 infected datasets in respect to age (data shown in ratio of cell numbers/per 1000 cells in age dataset) (n = P3, A4, O4). (f) Dot plots showing the log-fold change in SARS-CoV-2 versus mock at different time points for all cell types in different age groups. Calculation based upon absolute cell numbers with the average fold-change indicated by colour. The dot size corresponds to the number of that cell type per 1000 cells from each condition. (g) Uniform manifold approximation and projection (UMAP) representation of the results from Milo differential abundance testing. Nodes are neighbourhoods, coloured by their log fold change when comparing SARS-CoV-2 infected versus mock conditions in adult samples. Non-significant DA neighbourhoods at FDR 10% are coloured grey and significant DA neighbourhoods at FDR 10% are coloured with increased log fold change in red and decreased log fold change in blue. Node sizes correspond to the number of cells in a neighbourhood. The layout of nodes is determined by the position of the neighbourhood index cell in the UMAP. (h) Palantir inferred pseudotime probabilities of cycling basal cells differentiating into ciliated 1, basaloid-like 2 or goblet 2 inflammatory cells.

Extended Data Fig. 6 Basaloid-like cells were predominantly found in COVID-19 older adult patients in vivo.

(a) Dot plot visualisation showing marker genes for annotated epithelial cell types in the integrated in vivo single cell dataset (Fig. 2k ), with fraction of expressing cells and average expression within each cell type indicated by dot size and colour, respectively. Normalised goblet inflammatory cells (b) and basaloid-like 2 cells (c) per total of 5000 cells per age group in all paediatric, adult, and older adult subgroups. PF = pulmonary fibrosis, IPF = idiopathic pulmonary fibrosis. (Healthy dataset n = P49, A45, O46; COVID19 dataset n = P41, A58, O116).

Extended Data Fig. 7 Paediatric goblet 2 inflammatory cells and viral truncation in response to IFN signalling.

(a) Gene Set Enrichment Analysis (GSEA) of HVGs from goblet inflammatory cells indicating enriched gene ontology terms using ShinyGo. (b) Correlation matrix of a subset of interferon genes expressed by all paediatric or older adult cells at 72 h post SARS-CoV-2 infection as determined using the function cor_pmat() in ggcorrplot and Pearson correlation method. (c) ISG gene expression in SARS-CoV-2 infected cultures (as log-fold change compared to mock) per cell type at 4 h, 24 and 72 h p.i. for paediatric and older adult datasets. Barplot indicates the number of cells at each time point. Grey = not detected (d) Volcano plot showing differential expressed proteins of the apical secretome between mock and SARS-CoV-2 infected cultures that were unique (highly expressed) in the paediatric cohort. Blue highlights those that are highly expressed in mock compared to SARS-CoV-2 infection conditions and black enriched with infection. (e) GSEA for expression of apical secretome genes of paediatric cells at 72 h p.i. with SARS-CoV-2 obtained using ShinyGo. The data in a,b,c relates the scRNAseq dataset (n = P3, A4, O4), whilst d and e uses data generated through the analysis of the collected apical secretome (n = P5, A5, O5).

Extended Data Fig. 8 Viral truncation in response to IFN signaling.

Coverage plots of viral reads aligned to SARS-CoV-2 genome in each cell type in (a) paediatric, (b) adult (c) and older adult infected NECs grouped across all time points. Coverage plots of viral reads aligned to SARS-CoV-2 genome for all cell types, shown by age group, both (d) with and (e) without spiked-in primer grouped across all timepoints (see methods for more details of primer) and at (f) 72 h p.i. time points. Viral reads for all coverage plots are shown in 100 nucleotide (nt) bins normalised per 5,000 cells. The data in a - f relates to the scRNA-seq dataset (n = P3, A4, O4). (g) Histogram displaying frequency and position of genomic mutations in SARS-CoV-2 consensus sequences from 72 h p.i. with SARS-CoV-2 (n = P5, A5, O5). Bin size is 1000 bases (left) and 50 bases (right). Colour blocks indicate the start coordinates of annotated viral genes.

Extended Data Fig. 9 Elderly basaloid-like 2 cells drive ITGB6 production and enhance viral pathogenesis.

(a) Abundance of ITGB6 protein in the apical secretome of mock or SARS-CoV-2 infected NECs at 72 h p.i. for each age group (n = P5, A5, O5). As detected using mass spectrometry and shown in boxplot depicting the median and IQR, plus the minimum and maximum value distribution analysed using paired t test. (b) Exemplar Western blot showing vimentin (vim) in the older adult sample 72 h p.i. with mock (-) or SARS-CoV-2 (+) and 72 h p.i. Vero E6 cells as control lysate (ctl). GAPDH is the loading control, E-Cadherin is also given for reference (n = P2, A1, O1). (c) Orthogonal views of the z-stacks showing the location of ITGB6 (green) and KRT5+ve cells (white) from exemplar air–liquid interface cultures, counterstained for F-actin (phalloidin, red) and cell nucleus (DAPI, blue). (d) Representative maximum intensity projections (left) and orthogonal sections (right) of immunofluorescence z-stacks of basaloid-like 2 cell markers ITGB6 (green), KRT5 (white), spike (magenta) counterstained for F-actin (phalloidin; red) and cell nucleus (DAPI, blue) in 72 h p.i. NECs (mock top, infected bottom). (e-g) Further, example immunofluorescence images of basaloid-like 2 cell markers in 72 h p.i. with SARS-CoV-2 in older adult NEC cultures. Markers and respective counterstain colour are indicated (n = O3). (h) Transmission electron micrograph of non-basal KRT5+ve epithelial cell (white arrow) location within an NEC culture at 72 h p.i. with SARS-CoV-2. Scale is on the right of the image. For panels c-h , representative images were selected from older adult NEC cultures (n = 3) 72 hours post-infection (p.i.) with SARS-CoV for each antibody panel.

Extended Data Fig. 10 Wound repair promotes SARS-CoV-2 viral replication.

(a) Dotplot visualisation showing viral entry genes for all cell types, with fraction of expressing cells and average expression within each cell type indicated by dot size and colour, respectively. Appended bar graphs indicate absolute cell numbers per cell type. Data generated using the entire scRNAseq dataset (n = P3, A4, O4). (b) Example immunofluorescence orthogonal sections of basaloid-like 2 cell markers in unwounded or wounded older adult NECs 24 h p.i. with mock or SARS-CoV-2 infection. F-actin (Phalloidin; red), KRT5 (white), ITGB6 (cyan) and DAPI (blue). (c) Mean ± SD KRT5 fluorescence signal (RFU) around wound area in different age groups. From maximal projections of fixed NECs without (-) and with (+) wounds, 24 h post wounding (n = P3, A3, O3) (n = 6). (d) Maximum intensity projection image of a NEC culture unwounded and 24 h post wound. F-actin (Phalloidin; white), Vimentin (VIM) (yellow) and DAPI (blue). (e) Mean ± SD Vimentin fluorescence signal (RFU) around wound area in different age groups. From maximal projections of fixed NECs without (-) and with (+) wounds, 24 h post wound (n = P2, A1, O2). (f) Example immunofluorescence orthogonal sections of basaloid-like 2 cell markers in non-wounded or wounded NECs 24 h p.i. with mock or SARS-CoV-2 infection from a paediatric and older adult donor. Stained for F-actin (Phalloidin; red), ITGB6 (green), SARS-CoV-2 Spike protein (magenta), KRT5 (white) and composite with DAPI (blue). (g) Mean ± SD ITGB6 fluorescence signal (RFU) around wound area in different age groups. From maximal projections of fixed NECs without (-) and with (+) wounds, 24 h post wounding (n = P3, A3-4, O3-2). (h) Example of wound healing images taken of NECs from different age groups and with mock or SARS-CoV-2 infection. Acquired by light microscopy over 24 hours. The scale bar (bottom right) represents 1 mm. (i) Representative immunofluorescence images from 72 h p.i. NECs with SARS-CoV-2 without (-) and with (+) wounding stained for ITGB6 (cyan) and dsRNA (yellow). Percentage area covered (right) with ITGB6+ve or dsRNA+ve signal from maximum intensity projections of fixed NECs using threshold analysis (red) in ImageJ, the percentage coverage is given at the bottom right of each image. For c,e,g the average values for each NEC donor are shown and are subject to a two-way ANOVA with Sidak’s multiple comparisons test. For panels b, d, f, g, i a minimum of 5 experiments (ranging from n = 5–10) were conducted for each antibody panel, from which representative images were selected.

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Supplementary information.

Supplementary Figs. 1–3.

Reporting Summary

Supplementary tables.

Supplementary Tables 1–4.

Source Data Figs. 1–6

Statistical source data.

Source Data Extended Data Figs. 1–8 and 10

Source data extended data fig. 9.

Statistical source data and unprocessed Western blots.

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Woodall, M.N.J., Cujba, AM., Worlock, K.B. et al. Age-specific nasal epithelial responses to SARS-CoV-2 infection. Nat Microbiol (2024). https://doi.org/10.1038/s41564-024-01658-1

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6 Common Leadership Styles — and How to Decide Which to Use When

Rebecca Knight

Being a great leader means recognizing that different circumstances call for different approaches.

Research suggests that the most effective leaders adapt their style to different circumstances — be it a change in setting, a shift in organizational dynamics, or a turn in the business cycle. But what if you feel like you’re not equipped to take on a new and different leadership style — let alone more than one? In this article, the author outlines the six leadership styles Daniel Goleman first introduced in his 2000 HBR article, “Leadership That Gets Results,” and explains when to use each one. The good news is that personality is not destiny. Even if you’re naturally introverted or you tend to be driven by data and analysis rather than emotion, you can still learn how to adapt different leadership styles to organize, motivate, and direct your team.

Much has been written about common leadership styles and how to identify the right style for you, whether it’s transactional or transformational, bureaucratic or laissez-faire. But according to Daniel Goleman, a psychologist best known for his work on emotional intelligence, “Being a great leader means recognizing that different circumstances may call for different approaches.”

RK Rebecca Knight is a journalist who writes about all things related to the changing nature of careers and the workplace. Her essays and reported stories have been featured in The Boston Globe, Business Insider, The New York Times, BBC, and The Christian Science Monitor. She was shortlisted as a Reuters Institute Fellow at Oxford University in 2023. Earlier in her career, she spent a decade as an editor and reporter at the Financial Times in New York, London, and Boston.

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How to Write a Discussion Section
Table of contents. What not to include in your discussion section. Step 1: Summarize your key findings. Step 2: Give your interpretations. Step 3: Discuss the implications. Step 4: Acknowledge the limitations. Step 5: Share your recommendations. Discussion section example. Other interesting articles.
PDF Discussion Section for Research Papers
The discussion section is one of the final parts of a research paper, in which an author describes, analyzes, and interprets their findings. They explain the significance of those results and tie everything back to the research question(s). In this handout, you will find a description of what a discussion section does, explanations of how to ...
How to Write Discussions and Conclusions
Begin with a clear statement of the principal findings. This will reinforce the main take-away for the reader and set up the rest of the discussion. Explain why the outcomes of your study are important to the reader. Discuss the implications of your findings realistically based on previous literature, highlighting both the strengths and ...
8. The Discussion
The discussion section is often considered the most important part of your research paper because it: Most effectively demonstrates your ability as a researcher to think critically about an issue, to develop creative solutions to problems based upon a logical synthesis of the findings, and to formulate a deeper, more profound understanding of the research problem under investigation;
PDF 7th Edition Discussion Phrases Guide
Papers usually end with a concluding section, often called the "Discussion.". The Discussion is your opportunity to evaluate and interpret the results of your study or paper, draw inferences and conclusions from it, and communicate its contributions to science and/or society. Use the present tense when writing the Discussion section.
Discussion Section Examples and Writing Tips
This discussion example is from an engineering research paper. The authors are restating their aims first, which is to compare different types of storm-tracking software. Then, they are providing a brief summary of the methods. Here, they are testing different storm-tracking software under different conditions to see which performs the best.
How to Write a Discussion Section for a Research Paper
Begin the Discussion section by restating your statement of the problem and briefly summarizing the major results. Do not simply repeat your findings. Rather, try to create a concise statement of the main results that directly answer the central research question that you stated in the Introduction section.
How to Write the Discussion Section of a Research Paper
The discussion section provides an analysis and interpretation of the findings, compares them with previous studies, identifies limitations, and suggests future directions for research. This section combines information from the preceding parts of your paper into a coherent story. By this point, the reader already knows why you did your study ...
How to write a discussion section?
The discussion section can be written in 3 parts: an introductory paragraph, intermediate paragraphs and a conclusion paragraph. For intermediate paragraphs, a "divide and conquer" approach, meaning a full paragraph describing each of the study endpoints, can be used. In conclusion, academic writing is similar to other skills, and practice ...
How to Write a Discussion for a Research Paper: Expert Guide
Follow these steps for writing a good research paper discussion section. Summarize Findings: Begin with a concise summary of your main results. Interpret Results: Interpret and explain the meaning of your findings. Compare with Literature: Compare your results to existing literature.
Discussion Section of a Research Paper: Guide & Example
The discussion section of a research paper is where the author analyzes and explains the importance of the study's results. It presents the conclusions drawn from the study, compares them to previous research, and addresses any potential limitations or weaknesses. The discussion section should also suggest areas for future research.
How To Write A Dissertation Discussion Chapter
Step 1: Restate your research problem and research questions. The first step in writing up your discussion chapter is to remind your reader of your research problem, as well as your research aim (s) and research questions. If you have hypotheses, you can also briefly mention these.
Discussion
Discussion Section. The overall purpose of a research paper's discussion section is to evaluate and interpret results, while explaining both the implications and limitations of your findings. Per APA (2020) guidelines, this section requires you to "examine, interpret, and qualify the results and draw inferences and conclusions from them ...
How to Start a Discussion Section in Research? [with Examples]
The examples below are from 72,017 full-text PubMed research papers that I analyzed in order to explore common ways to start writing the Discussion section. Research papers included in this analysis were selected at random from those uploaded to PubMed Central between the years 2016 and 2021. Note that I used the BioC API to download the data ...
How to Write a Discussion Section of a Research Paper
Example of Discussion in Research Paper. Here is a short example for your inspiration: In the discussion section, we will delve deeper into the findings of our study and explore their implications. Our research showed a strong correlation between regular exercise and improved mental health. This finding is consistent with previous studies in ...
Organizing Academic Research Papers: 8. The Discussion
Organization and Structure. Keep the following sequential points in mind as you organize and write the discussion section of your paper: Think of your discussion as an inverted pyramid. Organize the discussion from the general to the specific, linking your findings to the literature, then to theory, then to practice [if appropriate]. Use the ...
How To Write a Discussion for a Research Paper in 7 Steps
Step 2: Interpret Your Results. In the next step, talk about what your findings really mean. Share why the information you gathered is important. Connect each result to the questions you were trying to answer and the goals you set for your research.
(PDF) How to Write an Effective Discussion
The discussion section, a systematic critical appraisal of results, is a key part of a research paper, wherein the authors define, critically examine, describe and interpret their findings ...
How to Write an Effective Discussion in a Research Paper; a Guide to
Discussion is mainly the section in a research paper that makes the readers understand the exact meaning of the results achieved in a study by exploring the significant points of the research, its ...
How to Write a Discussion For a Research Paper in 5 Steps
Step 2: Provide Interpretations. In this step, highlight why your findings matter and how they enhance our understanding of the research area. Use a mix of qualitative and quantitative techniques to comprehensively interpret results.
How to Write a Discussion Section
Table of contents. What not to include in your discussion section. Step 1: Summarise your key findings. Step 2: Give your interpretations. Step 3: Discuss the implications. Step 4: Acknowledge the limitations. Step 5: Share your recommendations. Discussion section example.
Guide to Writing the Results and Discussion Sections of a ...
Tips to Write the Results Section. Direct the reader to the research data and explain the meaning of the data. Avoid using a repetitive sentence structure to explain a new set of data. Write and highlight important findings in your results. Use the same order as the subheadings of the methods section.
Research Paper
The discussion section of a research paper interprets the findings and discusses their implications for the research question, the literature review, and the field of study. ... Research Paper Example. Note: The below example research paper is for illustrative purposes only and is not an actual research paper. Actual research papers may have ...
Age-specific nasal epithelial responses to SARS-CoV-2 infection
a, Schematic of method and model used to study SARS-CoV-2 infection of paediatric (P, <12 years), adult (A, 30-50 years) and older adult (O, >70 years) nasal epithelial cells. b, UMAP ...
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6 Common Leadership Styles
Summary. Research suggests that the most effective leaders adapt their style to different circumstances — be it a change in setting, a shift in organizational dynamics, or a turn in the business ...

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2. How should I structure my discussion section?

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3.1. An example of research summary in discussion

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How to Write a Discussion Section for a Research Paper

What is the Discussion section of a research paper?

What should I include in the Discussion section?

How to Write the Discussion Section

Technical writing elements

Discussion section organization

Discussion Part 1: Summarizing Key Findings

Phrase examples: Summarizing the results

Discussion Part 2: Interpreting the Findings

Discussion Part 3: Discussing the Implications

Phrase examples: Discussing the implications of the research

Step 4: Acknowledging the limitations

Phrase examples: Limitations sentence beginners

Discussion Part 5: Giving Recommendations for Further Research

Phrase examples: Recommendation sentence beginners

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How to Write the Discussion Section of a Research Paper

Discussion section: what is it, what it does

What is it?

Why is it necessary?

Adds context for your results

Shows what your results actually mean and real-world implications

What to include in your discussion (in the correct order)

Summary of key findings

Begin with key findings with supporting evidence

State clearly and concisely

Interpretation of results

Analyze and interpret your findings

Unexpected or contradictory results

Context and comparison with previous work

How your work compares or contrasts with previous work

How to divide this section into subsections

Limitations

Why limitations don’t have a negative connotation

How limitations add to a researcher's credibility

Implications and significance

Restate your hypothesis

How was it proven or disproven?

How your results contribute to the literature

Future implications of your research

Sample discussion section

How to make your discussion flow naturally

Ensure your structure and ideas are consistent and clearly communicated

How to write a discussion section?

Introduction

A) Approaches to general aspects of manuscript writing process:

2. How should the manuscript be written?

3. Which target journal should be selected?

4. Do we have to get a pre-peer review about the written manuscript?