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How to Write a Conclusion for Research Papers (with Examples)

The conclusion of a research paper is a crucial section that plays a significant role in the overall impact and effectiveness of your research paper. However, this is also the section that typically receives less attention compared to the introduction and the body of the paper. The conclusion serves to provide a concise summary of the key findings, their significance, their implications, and a sense of closure to the study. Discussing how can the findings be applied in real-world scenarios or inform policy, practice, or decision-making is especially valuable to practitioners and policymakers. The research paper conclusion also provides researchers with clear insights and valuable information for their own work, which they can then build on and contribute to the advancement of knowledge in the field.

The research paper conclusion should explain the significance of your findings within the broader context of your field. It restates how your results contribute to the existing body of knowledge and whether they confirm or challenge existing theories or hypotheses. Also, by identifying unanswered questions or areas requiring further investigation, your awareness of the broader research landscape can be demonstrated.

Remember to tailor the research paper conclusion to the specific needs and interests of your intended audience, which may include researchers, practitioners, policymakers, or a combination of these.

Table of Contents

What is a conclusion in a research paper, summarizing conclusion, editorial conclusion, externalizing conclusion, importance of a good research paper conclusion, how to write a conclusion for your research paper, research paper conclusion examples.

• How to write a research paper conclusion with Paperpal? 

Frequently Asked Questions

A conclusion in a research paper is the final section where you summarize and wrap up your research, presenting the key findings and insights derived from your study. The research paper conclusion is not the place to introduce new information or data that was not discussed in the main body of the paper. When working on how to conclude a research paper, remember to stick to summarizing and interpreting existing content. The research paper conclusion serves the following purposes: 1

• Warn readers of the possible consequences of not attending to the problem.
• Recommend specific course(s) of action.
• Restate key ideas to drive home the ultimate point of your research paper.
• Provide a “take-home” message that you want the readers to remember about your study.

Types of conclusions for research papers

In research papers, the conclusion provides closure to the reader. The type of research paper conclusion you choose depends on the nature of your study, your goals, and your target audience. I provide you with three common types of conclusions:

A summarizing conclusion is the most common type of conclusion in research papers. It involves summarizing the main points, reiterating the research question, and restating the significance of the findings. This common type of research paper conclusion is used across different disciplines.

An editorial conclusion is less common but can be used in research papers that are focused on proposing or advocating for a particular viewpoint or policy. It involves presenting a strong editorial or opinion based on the research findings and offering recommendations or calls to action.

An externalizing conclusion is a type of conclusion that extends the research beyond the scope of the paper by suggesting potential future research directions or discussing the broader implications of the findings. This type of conclusion is often used in more theoretical or exploratory research papers.

Align your conclusion’s tone with the rest of your research paper. Start Writing with Paperpal Now!  

The conclusion in a research paper serves several important purposes:

• Offers Implications and Recommendations : Your research paper conclusion is an excellent place to discuss the broader implications of your research and suggest potential areas for further study. It’s also an opportunity to offer practical recommendations based on your findings.
• Provides Closure : A good research paper conclusion provides a sense of closure to your paper. It should leave the reader with a feeling that they have reached the end of a well-structured and thought-provoking research project.
• Leaves a Lasting Impression : Writing a well-crafted research paper conclusion leaves a lasting impression on your readers. It’s your final opportunity to leave them with a new idea, a call to action, or a memorable quote.

Writing a strong conclusion for your research paper is essential to leave a lasting impression on your readers. Here’s a step-by-step process to help you create and know what to put in the conclusion of a research paper: 2

• Research Statement : Begin your research paper conclusion by restating your research statement. This reminds the reader of the main point you’ve been trying to prove throughout your paper. Keep it concise and clear.
• Key Points : Summarize the main arguments and key points you’ve made in your paper. Avoid introducing new information in the research paper conclusion. Instead, provide a concise overview of what you’ve discussed in the body of your paper.
• Address the Research Questions : If your research paper is based on specific research questions or hypotheses, briefly address whether you’ve answered them or achieved your research goals. Discuss the significance of your findings in this context.
• Significance : Highlight the importance of your research and its relevance in the broader context. Explain why your findings matter and how they contribute to the existing knowledge in your field.
• Implications : Explore the practical or theoretical implications of your research. How might your findings impact future research, policy, or real-world applications? Consider the “so what?” question.
• Future Research : Offer suggestions for future research in your area. What questions or aspects remain unanswered or warrant further investigation? This shows that your work opens the door for future exploration.
• Closing Thought : Conclude your research paper conclusion with a thought-provoking or memorable statement. This can leave a lasting impression on your readers and wrap up your paper effectively. Avoid introducing new information or arguments here.
• Proofread and Revise : Carefully proofread your conclusion for grammar, spelling, and clarity. Ensure that your ideas flow smoothly and that your conclusion is coherent and well-structured.

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Remember that a well-crafted research paper conclusion is a reflection of the strength of your research and your ability to communicate its significance effectively. It should leave a lasting impression on your readers and tie together all the threads of your paper. Now you know how to start the conclusion of a research paper and what elements to include to make it impactful, let’s look at a research paper conclusion sample.

How to write a research paper conclusion with Paperpal?

A research paper conclusion is not just a summary of your study, but a synthesis of the key findings that ties the research together and places it in a broader context. A research paper conclusion should be concise, typically around one paragraph in length. However, some complex topics may require a longer conclusion to ensure the reader is left with a clear understanding of the study’s significance. Paperpal, an AI writing assistant trusted by over 800,000 academics globally, can help you write a well-structured conclusion for your research paper. 

• Sign Up or Log In: Create a new Paperpal account or login with your details.  
• Navigate to Features : Once logged in, head over to the features’ side navigation pane. Click on Templates and you’ll find a suite of generative AI features to help you write better, faster.  
• Generate an outline: Under Templates, select ‘Outlines’. Choose ‘Research article’ as your document type.  
• Select your section: Since you’re focusing on the conclusion, select this section when prompted.  
• Choose your field of study: Identifying your field of study allows Paperpal to provide more targeted suggestions, ensuring the relevance of your conclusion to your specific area of research. 
• Provide a brief description of your study: Enter details about your research topic and findings. This information helps Paperpal generate a tailored outline that aligns with your paper’s content. 
• Generate the conclusion outline: After entering all necessary details, click on ‘generate’. Paperpal will then create a structured outline for your conclusion, to help you start writing and build upon the outline.  
• Write your conclusion: Use the generated outline to build your conclusion. The outline serves as a guide, ensuring you cover all critical aspects of a strong conclusion, from summarizing key findings to highlighting the research’s implications. 
• Refine and enhance: Paperpal’s ‘Make Academic’ feature can be particularly useful in the final stages. Select any paragraph of your conclusion and use this feature to elevate the academic tone, ensuring your writing is aligned to the academic journal standards. 

By following these steps, Paperpal not only simplifies the process of writing a research paper conclusion but also ensures it is impactful, concise, and aligned with academic standards. Sign up with Paperpal today and write your research paper conclusion 2x faster .  

The research paper conclusion is a crucial part of your paper as it provides the final opportunity to leave a strong impression on your readers. In the research paper conclusion, summarize the main points of your research paper by restating your research statement, highlighting the most important findings, addressing the research questions or objectives, explaining the broader context of the study, discussing the significance of your findings, providing recommendations if applicable, and emphasizing the takeaway message. The main purpose of the conclusion is to remind the reader of the main point or argument of your paper and to provide a clear and concise summary of the key findings and their implications. All these elements should feature on your list of what to put in the conclusion of a research paper to create a strong final statement for your work.

A strong conclusion is a critical component of a research paper, as it provides an opportunity to wrap up your arguments, reiterate your main points, and leave a lasting impression on your readers. Here are the key elements of a strong research paper conclusion: 1. Conciseness : A research paper conclusion should be concise and to the point. It should not introduce new information or ideas that were not discussed in the body of the paper. 2. Summarization : The research paper conclusion should be comprehensive enough to give the reader a clear understanding of the research’s main contributions. 3 . Relevance : Ensure that the information included in the research paper conclusion is directly relevant to the research paper’s main topic and objectives; avoid unnecessary details. 4 . Connection to the Introduction : A well-structured research paper conclusion often revisits the key points made in the introduction and shows how the research has addressed the initial questions or objectives. 5. Emphasis : Highlight the significance and implications of your research. Why is your study important? What are the broader implications or applications of your findings? 6 . Call to Action : Include a call to action or a recommendation for future research or action based on your findings.

The length of a research paper conclusion can vary depending on several factors, including the overall length of the paper, the complexity of the research, and the specific journal requirements. While there is no strict rule for the length of a conclusion, but it’s generally advisable to keep it relatively short. A typical research paper conclusion might be around 5-10% of the paper’s total length. For example, if your paper is 10 pages long, the conclusion might be roughly half a page to one page in length.

In general, you do not need to include citations in the research paper conclusion. Citations are typically reserved for the body of the paper to support your arguments and provide evidence for your claims. However, there may be some exceptions to this rule: 1. If you are drawing a direct quote or paraphrasing a specific source in your research paper conclusion, you should include a citation to give proper credit to the original author. 2. If your conclusion refers to or discusses specific research, data, or sources that are crucial to the overall argument, citations can be included to reinforce your conclusion’s validity.

The conclusion of a research paper serves several important purposes: 1. Summarize the Key Points 2. Reinforce the Main Argument 3. Provide Closure 4. Offer Insights or Implications 5. Engage the Reader. 6. Reflect on Limitations

Remember that the primary purpose of the research paper conclusion is to leave a lasting impression on the reader, reinforcing the key points and providing closure to your research. It’s often the last part of the paper that the reader will see, so it should be strong and well-crafted.

• Makar, G., Foltz, C., Lendner, M., & Vaccaro, A. R. (2018). How to write effective discussion and conclusion sections. Clinical spine surgery, 31(8), 345-346.
• Bunton, D. (2005). The structure of PhD conclusion chapters.  Journal of English for academic purposes ,  4 (3), 207-224.

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• 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

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In a short paper—even a research paper—you don’t need to provide an exhaustive summary as part of your conclusion. But you do need to make some kind of transition between your final body paragraph and your concluding paragraph. This may come in the form of a few sentences of summary. Or it may come in the form of a sentence that brings your readers back to your thesis or main idea and reminds your readers where you began and how far you have traveled.

So, for example, in a paper about the relationship between ADHD and rejection sensitivity, Vanessa Roser begins by introducing readers to the fact that researchers have studied the relationship between the two conditions and then provides her explanation of that relationship. Here’s her thesis: “While socialization may indeed be an important factor in RS, I argue that individuals with ADHD may also possess a neurological predisposition to RS that is exacerbated by the differing executive and emotional regulation characteristic of ADHD.”

In her final paragraph, Roser reminds us of where she started by echoing her thesis: “This literature demonstrates that, as with many other conditions, ADHD and RS share a delicately intertwined pattern of neurological similarities that is rooted in the innate biology of an individual’s mind, a connection that cannot be explained in full by the behavioral mediation hypothesis.”  

Highlight the “so what”  

At the beginning of your paper, you explain to your readers what’s at stake—why they should care about the argument you’re making. In your conclusion, you can bring readers back to those stakes by reminding them why your argument is important in the first place. You can also draft a few sentences that put those stakes into a new or broader context.

In the conclusion to her paper about ADHD and RS, Roser echoes the stakes she established in her introduction—that research into connections between ADHD and RS has led to contradictory results, raising questions about the “behavioral mediation hypothesis.”

She writes, “as with many other conditions, ADHD and RS share a delicately intertwined pattern of neurological similarities that is rooted in the innate biology of an individual’s mind, a connection that cannot be explained in full by the behavioral mediation hypothesis.”  

Leave your readers with the “now what”  

After the “what” and the “so what,” you should leave your reader with some final thoughts. If you have written a strong introduction, your readers will know why you have been arguing what you have been arguing—and why they should care. And if you’ve made a good case for your thesis, then your readers should be in a position to see things in a new way, understand new questions, or be ready for something that they weren’t ready for before they read your paper.

In her conclusion, Roser offers two “now what” statements. First, she explains that it is important to recognize that the flawed behavioral mediation hypothesis “seems to place a degree of fault on the individual. It implies that individuals with ADHD must have elicited such frequent or intense rejection by virtue of their inadequate social skills, erasing the possibility that they may simply possess a natural sensitivity to emotion.” She then highlights the broader implications for treatment of people with ADHD, noting that recognizing the actual connection between rejection sensitivity and ADHD “has profound implications for understanding how individuals with ADHD might best be treated in educational settings, by counselors, family, peers, or even society as a whole.”

To find your own “now what” for your essay’s conclusion, try asking yourself these questions:

• What can my readers now understand, see in a new light, or grapple with that they would not have understood in the same way before reading my paper? Are we a step closer to understanding a larger phenomenon or to understanding why what was at stake is so important?  
• What questions can I now raise that would not have made sense at the beginning of my paper? Questions for further research? Other ways that this topic could be approached?  
• Are there other applications for my research? Could my questions be asked about different data in a different context? Could I use my methods to answer a different question?  
• What action should be taken in light of this argument? What action do I predict will be taken or could lead to a solution?  
• What larger context might my argument be a part of?  

What to avoid in your conclusion  

• a complete restatement of all that you have said in your paper.  
• a substantial counterargument that you do not have space to refute; you should introduce counterarguments before your conclusion.  
• an apology for what you have not said. If you need to explain the scope of your paper, you should do this sooner—but don’t apologize for what you have not discussed in your paper.  
• fake transitions like “in conclusion” that are followed by sentences that aren’t actually conclusions. (“In conclusion, I have now demonstrated that my thesis is correct.”)
• picture_as_pdf Conclusions

Conclusions

What this handout is about.

This handout will explain the functions of conclusions, offer strategies for writing effective ones, help you evaluate conclusions you’ve drafted, and suggest approaches to avoid.

About conclusions

Introductions and conclusions can be difficult to write, but they’re worth investing time in. They can have a significant influence on a reader’s experience of your paper.

Just as your introduction acts as a bridge that transports your readers from their own lives into the “place” of your analysis, your conclusion can provide a bridge to help your readers make the transition back to their daily lives. Such a conclusion will help them see why all your analysis and information should matter to them after they put the paper down.

Your conclusion is your chance to have the last word on the subject. The conclusion allows you to have the final say on the issues you have raised in your paper, to synthesize your thoughts, to demonstrate the importance of your ideas, and to propel your reader to a new view of the subject. It is also your opportunity to make a good final impression and to end on a positive note.

Your conclusion can go beyond the confines of the assignment. The conclusion pushes beyond the boundaries of the prompt and allows you to consider broader issues, make new connections, and elaborate on the significance of your findings.

Your conclusion should make your readers glad they read your paper. Your conclusion gives your reader something to take away that will help them see things differently or appreciate your topic in personally relevant ways. It can suggest broader implications that will not only interest your reader, but also enrich your reader’s life in some way. It is your gift to the reader.

Strategies for writing an effective conclusion

One or more of the following strategies may help you write an effective conclusion:

• Play the “So What” Game. If you’re stuck and feel like your conclusion isn’t saying anything new or interesting, ask a friend to read it with you. Whenever you make a statement from your conclusion, ask the friend to say, “So what?” or “Why should anybody care?” Then ponder that question and answer it. Here’s how it might go: You: Basically, I’m just saying that education was important to Douglass. Friend: So what? You: Well, it was important because it was a key to him feeling like a free and equal citizen. Friend: Why should anybody care? You: That’s important because plantation owners tried to keep slaves from being educated so that they could maintain control. When Douglass obtained an education, he undermined that control personally. You can also use this strategy on your own, asking yourself “So What?” as you develop your ideas or your draft.
• Return to the theme or themes in the introduction. This strategy brings the reader full circle. For example, if you begin by describing a scenario, you can end with the same scenario as proof that your essay is helpful in creating a new understanding. You may also refer to the introductory paragraph by using key words or parallel concepts and images that you also used in the introduction.
• Synthesize, don’t summarize. Include a brief summary of the paper’s main points, but don’t simply repeat things that were in your paper. Instead, show your reader how the points you made and the support and examples you used fit together. Pull it all together.
• Include a provocative insight or quotation from the research or reading you did for your paper.
• Propose a course of action, a solution to an issue, or questions for further study. This can redirect your reader’s thought process and help them to apply your info and ideas to their own life or to see the broader implications.
• Point to broader implications. For example, if your paper examines the Greensboro sit-ins or another event in the Civil Rights Movement, you could point out its impact on the Civil Rights Movement as a whole. A paper about the style of writer Virginia Woolf could point to her influence on other writers or on later feminists.

Strategies to avoid

• Beginning with an unnecessary, overused phrase such as “in conclusion,” “in summary,” or “in closing.” Although these phrases can work in speeches, they come across as wooden and trite in writing.
• Stating the thesis for the very first time in the conclusion.
• Introducing a new idea or subtopic in your conclusion.
• Ending with a rephrased thesis statement without any substantive changes.
• Making sentimental, emotional appeals that are out of character with the rest of an analytical paper.
• Including evidence (quotations, statistics, etc.) that should be in the body of the paper.

Four kinds of ineffective conclusions

• The “That’s My Story and I’m Sticking to It” Conclusion. This conclusion just restates the thesis and is usually painfully short. It does not push the ideas forward. People write this kind of conclusion when they can’t think of anything else to say. Example: In conclusion, Frederick Douglass was, as we have seen, a pioneer in American education, proving that education was a major force for social change with regard to slavery.
• The “Sherlock Holmes” Conclusion. Sometimes writers will state the thesis for the very first time in the conclusion. You might be tempted to use this strategy if you don’t want to give everything away too early in your paper. You may think it would be more dramatic to keep the reader in the dark until the end and then “wow” them with your main idea, as in a Sherlock Holmes mystery. The reader, however, does not expect a mystery, but an analytical discussion of your topic in an academic style, with the main argument (thesis) stated up front. Example: (After a paper that lists numerous incidents from the book but never says what these incidents reveal about Douglass and his views on education): So, as the evidence above demonstrates, Douglass saw education as a way to undermine the slaveholders’ power and also an important step toward freedom.
• The “America the Beautiful”/”I Am Woman”/”We Shall Overcome” Conclusion. This kind of conclusion usually draws on emotion to make its appeal, but while this emotion and even sentimentality may be very heartfelt, it is usually out of character with the rest of an analytical paper. A more sophisticated commentary, rather than emotional praise, would be a more fitting tribute to the topic. Example: Because of the efforts of fine Americans like Frederick Douglass, countless others have seen the shining beacon of light that is education. His example was a torch that lit the way for others. Frederick Douglass was truly an American hero.
• The “Grab Bag” Conclusion. This kind of conclusion includes extra information that the writer found or thought of but couldn’t integrate into the main paper. You may find it hard to leave out details that you discovered after hours of research and thought, but adding random facts and bits of evidence at the end of an otherwise-well-organized essay can just create confusion. Example: In addition to being an educational pioneer, Frederick Douglass provides an interesting case study for masculinity in the American South. He also offers historians an interesting glimpse into slave resistance when he confronts Covey, the overseer. His relationships with female relatives reveal the importance of family in the slave community.

Works consulted

We consulted these works while writing this handout. This is not a comprehensive list of resources on the handout’s topic, and we encourage you to do your own research to find additional publications. Please do not use this list as a model for the format of your own reference list, as it may not match the citation style you are using. For guidance on formatting citations, please see the UNC Libraries citation tutorial . We revise these tips periodically and welcome feedback.

Douglass, Frederick. 1995. Narrative of the Life of Frederick Douglass, an American Slave, Written by Himself. New York: Dover.

Hamilton College. n.d. “Conclusions.” Writing Center. Accessed June 14, 2019. https://www.hamilton.edu//academics/centers/writing/writing-resources/conclusions .

Holewa, Randa. 2004. “Strategies for Writing a Conclusion.” LEO: Literacy Education Online. Last updated February 19, 2004. https://leo.stcloudstate.edu/acadwrite/conclude.html.

You may reproduce it for non-commercial use if you use the entire handout and attribute the source: The Writing Center, University of North Carolina at Chapel Hill

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Research Paper Conclusion – Writing Guide and Examples

Table of Contents

Research Paper Conclusion

Definition:

A research paper conclusion is the final section of a research paper that summarizes the key findings, significance, and implications of the research. It is the writer’s opportunity to synthesize the information presented in the paper, draw conclusions, and make recommendations for future research or actions.

The conclusion should provide a clear and concise summary of the research paper, reiterating the research question or problem, the main results, and the significance of the findings. It should also discuss the limitations of the study and suggest areas for further research.

Parts of Research Paper Conclusion

The parts of a research paper conclusion typically include:

Restatement of the Thesis

The conclusion should begin by restating the thesis statement from the introduction in a different way. This helps to remind the reader of the main argument or purpose of the research.

Summary of Key Findings

The conclusion should summarize the main findings of the research, highlighting the most important results and conclusions. This section should be brief and to the point.

Implications and Significance

In this section, the researcher should explain the implications and significance of the research findings. This may include discussing the potential impact on the field or industry, highlighting new insights or knowledge gained, or pointing out areas for future research.

Limitations and Recommendations

It is important to acknowledge any limitations or weaknesses of the research and to make recommendations for how these could be addressed in future studies. This shows that the researcher is aware of the potential limitations of their work and is committed to improving the quality of research in their field.

Concluding Statement

The conclusion should end with a strong concluding statement that leaves a lasting impression on the reader. This could be a call to action, a recommendation for further research, or a final thought on the topic.

How to Write Research Paper Conclusion

Here are some steps you can follow to write an effective research paper conclusion:

• Restate the research problem or question: Begin by restating the research problem or question that you aimed to answer in your research. This will remind the reader of the purpose of your study.
• Summarize the main points: Summarize the key findings and results of your research. This can be done by highlighting the most important aspects of your research and the evidence that supports them.
• Discuss the implications: Discuss the implications of your findings for the research area and any potential applications of your research. You should also mention any limitations of your research that may affect the interpretation of your findings.
• Provide a conclusion : Provide a concise conclusion that summarizes the main points of your paper and emphasizes the significance of your research. This should be a strong and clear statement that leaves a lasting impression on the reader.
• Offer suggestions for future research: Lastly, offer suggestions for future research that could build on your findings and contribute to further advancements in the field.

Remember that the conclusion should be brief and to the point, while still effectively summarizing the key findings and implications of your research.

Example of Research Paper Conclusion

Here’s an example of a research paper conclusion:

Conclusion :

In conclusion, our study aimed to investigate the relationship between social media use and mental health among college students. Our findings suggest that there is a significant association between social media use and increased levels of anxiety and depression among college students. This highlights the need for increased awareness and education about the potential negative effects of social media use on mental health, particularly among college students.

Despite the limitations of our study, such as the small sample size and self-reported data, our findings have important implications for future research and practice. Future studies should aim to replicate our findings in larger, more diverse samples, and investigate the potential mechanisms underlying the association between social media use and mental health. In addition, interventions should be developed to promote healthy social media use among college students, such as mindfulness-based approaches and social media detox programs.

Overall, our study contributes to the growing body of research on the impact of social media on mental health, and highlights the importance of addressing this issue in the context of higher education. By raising awareness and promoting healthy social media use among college students, we can help to reduce the negative impact of social media on mental health and improve the well-being of young adults.

Purpose of Research Paper Conclusion

The purpose of a research paper conclusion is to provide a summary and synthesis of the key findings, significance, and implications of the research presented in the paper. The conclusion serves as the final opportunity for the writer to convey their message and leave a lasting impression on the reader.

The conclusion should restate the research problem or question, summarize the main results of the research, and explain their significance. It should also acknowledge the limitations of the study and suggest areas for future research or action.

Overall, the purpose of the conclusion is to provide a sense of closure to the research paper and to emphasize the importance of the research and its potential impact. It should leave the reader with a clear understanding of the main findings and why they matter. The conclusion serves as the writer’s opportunity to showcase their contribution to the field and to inspire further research and action.

When to Write Research Paper Conclusion

The conclusion of a research paper should be written after the body of the paper has been completed. It should not be written until the writer has thoroughly analyzed and interpreted their findings and has written a complete and cohesive discussion of the research.

Before writing the conclusion, the writer should review their research paper and consider the key points that they want to convey to the reader. They should also review the research question, hypotheses, and methodology to ensure that they have addressed all of the necessary components of the research.

Once the writer has a clear understanding of the main findings and their significance, they can begin writing the conclusion. The conclusion should be written in a clear and concise manner, and should reiterate the main points of the research while also providing insights and recommendations for future research or action.

Characteristics of Research Paper Conclusion

The characteristics of a research paper conclusion include:

• Clear and concise: The conclusion should be written in a clear and concise manner, summarizing the key findings and their significance.
• Comprehensive: The conclusion should address all of the main points of the research paper, including the research question or problem, the methodology, the main results, and their implications.
• Future-oriented : The conclusion should provide insights and recommendations for future research or action, based on the findings of the research.
• Impressive : The conclusion should leave a lasting impression on the reader, emphasizing the importance of the research and its potential impact.
• Objective : The conclusion should be based on the evidence presented in the research paper, and should avoid personal biases or opinions.
• Unique : The conclusion should be unique to the research paper and should not simply repeat information from the introduction or body of the paper.

Advantages of Research Paper Conclusion

The advantages of a research paper conclusion include:

• Summarizing the key findings : The conclusion provides a summary of the main findings of the research, making it easier for the reader to understand the key points of the study.
• Emphasizing the significance of the research: The conclusion emphasizes the importance of the research and its potential impact, making it more likely that readers will take the research seriously and consider its implications.
• Providing recommendations for future research or action : The conclusion suggests practical recommendations for future research or action, based on the findings of the study.
• Providing closure to the research paper : The conclusion provides a sense of closure to the research paper, tying together the different sections of the paper and leaving a lasting impression on the reader.
• Demonstrating the writer’s contribution to the field : The conclusion provides the writer with an opportunity to showcase their contribution to the field and to inspire further research and action.

Limitations of Research Paper Conclusion

While the conclusion of a research paper has many advantages, it also has some limitations that should be considered, including:

• I nability to address all aspects of the research: Due to the limited space available in the conclusion, it may not be possible to address all aspects of the research in detail.
• Subjectivity : While the conclusion should be objective, it may be influenced by the writer’s personal biases or opinions.
• Lack of new information: The conclusion should not introduce new information that has not been discussed in the body of the research paper.
• Lack of generalizability: The conclusions drawn from the research may not be applicable to other contexts or populations, limiting the generalizability of the study.
• Misinterpretation by the reader: The reader may misinterpret the conclusions drawn from the research, leading to a misunderstanding of the findings.

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How to Write a Conclusion for a Research Paper

By the time you write the conclusion, you should have pointed out in the body of your research paper why your topic is important to the reader, and you should have presented the reader with all your arguments. It is critical that you do not introduce new information or ideas in your conclusion. If you find that you have not yet made the arguments you wished to make or pointed out evidence you feel is crucial to your reader’s understanding of your subject, you are not yet ready to write the conclusion; add another body paragraph before writing the conclusion.

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Your research paper should have a strong, succinct concluding section, where you draw together your findings. Think of it as a conclusion, not a summary. The difference is that you are reaching overall judgments about your topic, not summarizing everything you wrote about it. How to write a conclusion for a research paper? The focus should be on:

• Saying what your research has found, what the findings mean, and how well they support the argument of your thesis statement.
• Establishing the limits of your argument: How widely does it apply? What are the strengths and weaknesses of your method? How clear-cut are your findings?
• Explaining how your findings and argument fit into your field, relating them to answers others have given and to the existing literature.

You may also want to add some concise comments about possible future developments or what kind of research should come next, but don’t lay it on too thick. The place of honor goes to your own explanation. Don’t spend too much of your final section criticizing others. Don’t introduce any big new topics or ideas. You certainly don’t expect to see new characters in the last scene of a movie. For the same reasons, you shouldn’t find any big new topics being introduced in the last paragraphs of a research paper.

Your concluding statement should focus on what your findings mean. How do you interpret them? Are they just as easily explained by alternative theories or other perspectives? Here, you are returning to the questions that first animated you and answering them, based on your research. You not only want to give the answers; you also want to explain their significance. What do they mean for policy, theory, literary interpretation, moral action, or whatever? You are answering the old, hard question: “So what?”

Be wary of overreaching. You really need to do two things at the same time: explain the significance of your findings and stake out their limits. You may have a hunch that your findings apply widely but, as a social scientist, you need to assess whether you can say so confidently, based on your current research. Your reader needs to know: “Do these findings apply to all college students, to all adults, or only to white mice?” White mice don’t come up much in the humanities, but the reader still wants to know how far your approach reaches. Does your analysis apply only to this novel or this writer, or could it apply to a whole literary genre?

Make it a priority to discuss these conclusions with your professor or adviser. The main danger here is that students finally reach this final section with only a week or two left before the due date. They don’t have enough time to work through their conclusions and revise them. That leaves the research paper weakest at the end, precisely where it should be strongest, nailing down the most significant points.

Begin discussing your major findings with your adviser while you are still writing the heart of the research paper. Of course, your conclusions will be tentative at that stage, but it helps to begin talking about them. As always, a little writing helps. You could simply list your main findings or write out a few paragraphs about them. Either would serve as a launching pad for meetings with your adviser. You will find these discussions also shed light on the research that leads to these findings. That, in turn, will strengthen your middle sections. Later, when you draft the conclusion, review your notes on these talks and the short documents you wrote for them. They will serve as prewriting for the final section.

The opening sentence of the conclusion should flow smoothly and logically from the transition sentence in the previous paragraph and lead the reader to reflect on your thesis. A good conclusion however, does not simply restate the thesis. You want to remind the reader of the thesis in your conclusion but reword it in a stronger fashion so that it is interesting and memorable to your audience.After reminding the reader of the thesis, the conclusion should then reflect on the topics in the body of the paper and summarize the key findings of your research. If you are writing a persuasive paper, it should summarize your key arguments and logically point your readers to the conclusion you wish them to reach.

Phrases for Conclusions of Research Papers

• All this requires us to (propose the next action or an alternative idea).
• Altogether, these findings indicate (point out the logical result).
• Finally, it is important to note (make your strongest point and follow with a recommendation).
• In conclusion (restate your thesis with greater emphasis).
• It is evident that (point out the logical result or obvious next action).
• In light of the evidence, (restate your thesis with greater emphasis).
• In short, (summarize your findings).
• It should be evident that we need to (propose the next action or an alternative idea).
• In summary, (summarize your findings).
• Looking ahead, it is obvious that (propose the next action or an alternative idea).
• My conclusion is (restate your thesis with greater emphasis).
• One last word must be said. (Follow with your opinion and propose a next action.)
• One concludes that (give your opinion).
• Overall, (summarize your findings).
• Reflecting on these facts,we can see that …
• The evidence presented above shows that (give your opinion).
• The reader can conclude (make the point you wish to make).
• These facts and observations support the idea that (offer a theory).
• This analysis reveals (state your findings).
• To conclude, (give an opinion based on the findings presented in the paper).
• To sum up this discussion, (summarize your findings).
• To summarize, (summarize your findings).
• We arrive at the following conclusion: (give an opinion based on the findings presented in the paper).
• We cannot ignore the fact that (state an important concern and follow with a call to action).
• We can postulate (give your opinion or offer a theory).
• We come to the conclusion that (give your opinion or offer a theory).
• We can now present the theory that (give your opinion or offer a theory).

Examples of Strong Conclusions

As an example of how to end your research paper, let’s turn again to John Dower’s splendid book on postwar Japan, Embracing Defeat: Japan in the Wake of World War II . In the final pages, Dower pulls together his findings on war-ravaged Japan and its efforts to rebuild. He then judges the legacies of that period: its continuing impact on the country’s social, political, and economic life. Some insights are unexpected, at least to me. He argues that Japan has pursued trade protection as the only acceptable avenue for its persistent nationalism. America’s overwhelming power and Japan’s self-imposed restraints—the intertwined subjects of the book—blocked any political or military expression of Japan’s nationalist sentiment. Those avenues were simply too dangerous, he says, while economic nationalism was not. Dower ends with these paragraphs:

The Japanese economists and bureaucrats who drafted the informal 1946 blueprint for a planned economy were admirably clear on these objectives [of “demilitarization and democratization”]. They sought rapid recovery and maximum economic growth, of course—but they were just as concerned with achieving economic demilitarization and economic democracy. . . . Japan became wealthy. The standard of living rose impressively at every level of society. Income distribution was far more equitable than in the United States. Job security was assured. Growth was achieved without inordinate dependence on a military-industrial complex or a thriving trade in armaments. These are hardly trivial ideas, but they are now being discarded along with all the deservedly bankrupt aspects of the postwar system. The lessons and legacies of defeat have been many and varied indeed; and their end is not yet in sight. (John W. Dower, Embracing Defeat: Japan in the Wake of World War II . New York: W. W. Norton, 1999, pp. 563–64)

Remember the anecdotal opening of Herbert’s book Impressionism: Art, Leisure, and Parisian Society , with Henry Tuckerman’s 1867 arrival in a much-changed Paris? (see research paper introduction examples) Herbert strikes a completely different tone in his conclusion. It synthesizes the art history he has presented, offers a large judgment about where Impressionism fits among art movements, and suggests why exhibitions of Monet, Manet, and Renoir are still so popular. He manages to do all that in a few well-crafted sentences:

Although we credit [Impressionism] with being the gateway to modern art, we also treat it as the last of the great Western styles based upon a perception of harmony with natural vision. That harmony, long since lost to us in this century of urbanization, industrialization, and world wars, remains a longed-for idea, so we look back to Impressionism as the painting of a golden era. We flock into exhibitions of paintings that represent cafes, boating, promenading, and peaceful landscapes precisely because of our yearning for less troubled times. The only history that we feel deeply is the kind that is useful to us. Impressionism still looms large at the end of the twentieth century because we use its leisure-time subjects and its brilliantly colored surfaces to construct a desirable history. (Herbert, Impressionism , p. 306)

Robert Dallek offers similarly accessible, powerful judgments in his conclusion to Flawed Giant: Lyndon Johnson and His Times, 1961–1973 :

[Johnson’s] presidency was a story of great achievement and terrible failure, of lasting gains and unforgettable losses. . . . In a not so distant future, when coming generations have no direct experience of the man and the passions of the sixties are muted, Johnson will probably be remembered as a President who faithfully reflected the country’s greatness and limitations—a man notable for his successes and failures, for his triumphs and tragedy. Only one thing seems certain: Lyndon Johnson will not join the many obscure—almost nameless, faceless—Presidents whose terms of office register on most Americans as blank slates. He will not be forgotten. (Robert Dallek, Flawed Giant: Lyndon Johnson and His Times, 1961–1973 . New York: Oxford University Press, 1998, p. 628)

Some writers not only synthesize their findings or compare them to others; they use the conclusion to say what their work means for appropriate methods or subject matter in their field. That is what Robert Bruegmann does in his final statement in The Architects and the City: Holabird & Roche of Chicago, 1880–1918 . His conclusion goes beyond saying that this was a great architectural firm or that it designed buildings of lasting importance. Bruegmann tells us that Holabird & Roche helped shape modern Chicago and that its work, properly studied, helps us understand “the city as the ultimate human artifact”:

Traditional architectural history has tended to see the city less as a process than as a product, a collection of high art architectural objects in a setting dominated by mundane buildings of little interest. This tended to perpetuate a destructive and divisive attitude about the built environment, suggesting that only a few buildings are worthy of careful study and preservation while all others are mere backdrop. I hope that these explorations in the work of Holabird & Roche have shed light on parts of the city rarely visited by the architectural historian and on some little explored aspects of its history. If so, perhaps it has achieved its most basic goal: providing an insight into the city as the ultimate human artifact, our most complex and prodigious social creation, and the most tangible result of the actions over time of all its citizens. (Robert Bruegmann, The Architects and the City: Holabird & Roche of Chicago, 1880–1918 . Chicago: University of Chicago Press, 1997, p. 443)

These are powerful conclusions, ending major works of scholarship on a high note. What concluding paragraphs should never do is gaze off into the sunset, offer vague homilies, or claim you have found the meaning of human existence. Be concrete. Stick to your topic. Make sure your research paper conclusions stand on solid ground. Avoid vague platitudes in your conclusion. Your goal should be reaching strong, sound judgments, firmly grounded in your readings and research. Better to claim too little than too much. Best of all, claim what you’ve earned the right to say: what your research really means.

Having finished the main parts of a research paper you can write an abstract.

Back to  How To Write A Research Paper .

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How to Write a Conclusion for a Research Paper

Last Updated: May 8, 2024 Approved

This article was co-authored by Christopher Taylor, PhD . Christopher Taylor is an Adjunct Assistant Professor of English at Austin Community College in Texas. He received his PhD in English Literature and Medieval Studies from the University of Texas at Austin in 2014. wikiHow marks an article as reader-approved once it receives enough positive feedback. This article received 42 testimonials and 83% of readers who voted found it helpful, earning it our reader-approved status. This article has been viewed 2,259,999 times.

The conclusion of a research paper needs to summarize the content and purpose of the paper without seeming too wooden or dry. Every basic conclusion must share several key elements, but there are also several tactics you can play around with to craft a more effective conclusion and several you should avoid to prevent yourself from weakening your paper's conclusion. Here are some writing tips to keep in mind when creating a conclusion for your next research paper.

Sample Conclusions

Writing a basic conclusion.

• Do not spend a great amount of time or space restating your topic.
• A good research paper will make the importance of your topic apparent, so you do not need to write an elaborate defense of your topic in the conclusion.
• Usually a single sentence is all you need to restate your topic.
• An example would be if you were writing a paper on the epidemiology of infectious disease, you might say something like "Tuberculosis is a widespread infectious disease that affects millions of people worldwide every year."
• Yet another example from the humanities would be a paper about the Italian Renaissance: "The Italian Renaissance was an explosion of art and ideas centered around artists, writers, and thinkers in Florence."

• A thesis is a narrowed, focused view on the topic at hand.
• This statement should be rephrased from the thesis you included in your introduction. It should not be identical or too similar to the sentence you originally used.
• Try re-wording your thesis statement in a way that complements your summary of the topic of your paper in your first sentence of your conclusion.
• An example of a good thesis statement, going back to the paper on tuberculosis, would be "Tuberculosis is a widespread disease that affects millions of people worldwide every year. Due to the alarming rate of the spread of tuberculosis, particularly in poor countries, medical professionals are implementing new strategies for the diagnosis, treatment, and containment of this disease ."

• A good way to go about this is to re-read the topic sentence of each major paragraph or section in the body of your paper.
• Find a way to briefly restate each point mentioned in each topic sentence in your conclusion. Do not repeat any of the supporting details used within your body paragraphs.
• Under most circumstances, you should avoid writing new information in your conclusion. This is especially true if the information is vital to the argument or research presented in your paper.
• For example, in the TB paper you could summarize the information. "Tuberculosis is a widespread disease that affects millions of people worldwide. Due to the alarming rate of the spread of tuberculosis, particularly in poor countries, medical professionals are implementing new strategies for the diagnosis, treatment, and containment of this disease. In developing countries, such as those in Africa and Southeast Asia, the rate of TB infections is soaring. Crowded conditions, poor sanitation, and lack of access to medical care are all compounding factors in the spread of the disease. Medical experts, such as those from the World Health Organization are now starting campaigns to go into communities in developing countries and provide diagnostic testing and treatments. However, the treatments for TB are very harsh and have many side effects. This leads to patient non-compliance and spread of multi-drug resistant strains of the disease."

• Note that this is not needed for all research papers.
• If you already fully explained what the points in your paper mean or why they are significant, you do not need to go into them in much detail in your conclusion. Simply restating your thesis or the significance of your topic should suffice.
• It is always best practice to address important issues and fully explain your points in the body of your paper. The point of a conclusion to a research paper is to summarize your argument for the reader and, perhaps, to call the reader to action if needed.

• Note that a call for action is not essential to all conclusions. A research paper on literary criticism, for instance, is less likely to need a call for action than a paper on the effect that television has on toddlers and young children.
• A paper that is more likely to call readers to action is one that addresses a public or scientific need. Let's go back to our example of tuberculosis. This is a very serious disease that is spreading quickly and with antibiotic-resistant forms.
• A call to action in this research paper would be a follow-up statement that might be along the lines of "Despite new efforts to diagnose and contain the disease, more research is needed to develop new antibiotics that will treat the most resistant strains of tuberculosis and ease the side effects of current treatments."

• For example, if you are writing a history paper, then you might discuss how the historical topic you discussed matters today. If you are writing about a foreign country, then you might use the conclusion to discuss how the information you shared may help readers understand their own country.

Making Your Conclusion as Effective as Possible

• Since this sort of conclusion is so basic, you must aim to synthesize the information rather than merely summarizing it.
• Instead of merely repeating things you already said, rephrase your thesis and supporting points in a way that ties them all together.
• By doing so, you make your research paper seem like a "complete thought" rather than a collection of random and vaguely related ideas.

• Ask a question in your introduction. In your conclusion, restate the question and provide a direct answer.
• Write an anecdote or story in your introduction but do not share the ending. Instead, write the conclusion to the anecdote in the conclusion of your paper.
• For example, if you wanted to get more creative and put a more humanistic spin on a paper on tuberculosis, you might start your introduction with a story about a person with the disease, and refer to that story in your conclusion. For example, you could say something like this before you re-state your thesis in your conclusion: "Patient X was unable to complete the treatment for tuberculosis due to severe side effects and unfortunately succumbed to the disease."
• Use the same concepts and images introduced in your introduction in your conclusion. The images may or may not appear at other points throughout the research paper.

• Include enough information about your topic to back the statement up but do not get too carried away with excess detail.
• If your research did not provide you with a clear-cut answer to a question posed in your thesis, do not be afraid to indicate as much.
• Restate your initial hypothesis and indicate whether you still believe it or if the research you performed has begun swaying your opinion.
• Indicate that an answer may still exist and that further research could shed more light on the topic at hand.

• This may not be appropriate for all types of research papers. Most research papers, such as one on effective treatment for diseases, will have the information to make the case for a particular argument already in the paper.
• A good example of a paper that might ask a question of the reader in the ending is one about a social issue, such as poverty or government policy.
• Ask a question that will directly get at the heart or purpose of the paper. This question is often the same question, or some version of it, that you may have started with when you began your research.
• Make sure that the question can be answered by the evidence presented in your paper.
• If desired you can briefly summarize the answer after stating the question. You could also leave the question hanging for the reader to answer, though.

• Even without a call to action, you can still make a recommendation to your reader.
• For instance, if you are writing about a topic like third-world poverty, you can various ways for the reader to assist in the problem without necessarily calling for more research.
• Another example would be, in a paper about treatment for drug-resistant tuberculosis, you could suggest donating to the World Health Organization or research foundations that are developing new treatments for the disease.

Avoiding Common Pitfalls

• These sayings usually sound stiff, unnatural, or trite when used in writing.
• Moreover, using a phrase like "in conclusion" to begin your conclusion is a little too straightforward and tends to lead to a weak conclusion. A strong conclusion can stand on its own without being labeled as such.

• Always state the main argument or thesis in the introduction. A research paper is an analytical discussion of an academic topic, not a mystery novel.
• A good, effective research paper will allow your reader to follow your main argument from start to finish.
• This is why it is best practice to start your paper with an introduction that states your main argument and to end the paper with a conclusion that re-states your thesis for re-iteration.

• All significant information should be introduced in the body of the paper.
• Supporting evidence expands the topic of your paper by making it appear more detailed. A conclusion should narrow the topic to a more general point.
• A conclusion should only summarize what you have already stated in the body of your paper.
• You may suggest further research or a call to action, but you should not bring in any new evidence or facts in the conclusion.

• Most often, a shift in tone occurs when a research paper with an academic tone gives an emotional or sentimental conclusion.
• Even if the topic of the paper is of personal significance for you, you should not indicate as much in your paper.
• If you want to give your paper a more humanistic slant, you could start and end your paper with a story or anecdote that would give your topic more personal meaning to the reader.
• This tone should be consistent throughout the paper, however.

• Apologetic statements include phrases like "I may not be an expert" or "This is only my opinion."
• Statements like this can usually be avoided by refraining from writing in the first-person.
• Avoid any statements in the first-person. First-person is generally considered to be informal and does not fit with the formal tone of a research paper.

Community Q&A

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• ↑ http://owl.english.purdue.edu/owl/resource/724/04/
• ↑ http://www.crlsresearchguide.org/18_Writing_Conclusion.asp
• ↑ http://writing.wisc.edu/Handbook/PlanResearchPaper.html#conclusion
• ↑ http://writingcenter.unc.edu/handouts/conclusions/
• ↑ http://writing2.richmond.edu/writing/wweb/conclude.html

About This Article

To write a conclusion for a research paper, start by restating your thesis statement to remind your readers what your main topic is and bring everything full circle. Then, briefly summarize all of the main points you made throughout your paper, which will help remind your readers of everything they learned. You might also want to include a call to action if you think more research or work needs to be done on your topic by writing something like, "Despite efforts to contain the disease, more research is needed to develop antibiotics." Finally, end your conclusion by explaining the broader context of your topic and why your readers should care about it, which will help them understand why your topic is relevant and important. For tips from our Academic co-author, like how to avoid common pitfalls when writing your conclusion, scroll down! Did this summary help you? Yes No

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Writing a Paper: Conclusions

Writing a conclusion.

A conclusion is an important part of the paper; it provides closure for the reader while reminding the reader of the contents and importance of the paper. It accomplishes this by stepping back from the specifics in order to view the bigger picture of the document. In other words, it is reminding the reader of the main argument. For most course papers, it is usually one paragraph that simply and succinctly restates the main ideas and arguments, pulling everything together to help clarify the thesis of the paper. A conclusion does not introduce new ideas; instead, it should clarify the intent and importance of the paper. It can also suggest possible future research on the topic.

An Easy Checklist for Writing a Conclusion

It is important to remind the reader of the thesis of the paper so he is reminded of the argument and solutions you proposed.

Think of the main points as puzzle pieces, and the conclusion is where they all fit together to create a bigger picture. The reader should walk away with the bigger picture in mind.

Make sure that the paper places its findings in the context of real social change.

Make sure the reader has a distinct sense that the paper has come to an end. It is important to not leave the reader hanging. (You don’t want her to have flip-the-page syndrome, where the reader turns the page, expecting the paper to continue. The paper should naturally come to an end.)

No new ideas should be introduced in the conclusion. It is simply a review of the material that is already present in the paper. The only new idea would be the suggesting of a direction for future research.

Conclusion Example

As addressed in my analysis of recent research, the advantages of a later starting time for high school students significantly outweigh the disadvantages. A later starting time would allow teens more time to sleep--something that is important for their physical and mental health--and ultimately improve their academic performance and behavior. The added transportation costs that result from this change can be absorbed through energy savings. The beneficial effects on the students’ academic performance and behavior validate this decision, but its effect on student motivation is still unknown. I would encourage an in-depth look at the reactions of students to such a change. This sort of study would help determine the actual effects of a later start time on the time management and sleep habits of students.

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How to Write a Conclusion for a Research Paper

When you're wrapping up a research paper, the conclusion is like the grand finale of a fireworks show – it's your chance to leave a lasting impression. In this article, we'll break down the steps to help you write a winning research paper conclusion that not only recaps your main points but also ties everything together. Consider it the "So what?" moment – why should people care about your research? Our professional essay writers will guide you through making your conclusion strong, clear, and something that sticks with your readers long after they've put down your paper. So, let's dive in and ensure your research ends on a high note!

What Is a Conclusion in a Research Paper

In a research paper, the conclusion serves as the final segment, where you summarize the main points and findings of your study. It's not just a repetition of what you've already said but rather a chance to tie everything together and highlight the significance of your research. As you learn how to start a research paper , a good conclusion also often discusses the implications of your findings, suggests potential areas for further research, and leaves the reader with a lasting impression of the importance and relevance of your work in the broader context of the field. Essentially, it's your last opportunity to make a strong impact and leave your readers with a clear understanding of the significance of your research. Here’s a research paper conclusion example:

In conclusion, this research paper has navigated the intricacies of sustainable urban development, shedding light on the pivotal role of community engagement and innovative planning strategies. Through applying qualitative and quantitative research methods, we've uncovered valuable insights into the challenges and opportunities inherent in fostering environmentally friendly urban spaces. The implications of these findings extend beyond the confines of this study, emphasizing the imperative for continued exploration in the realms of urban planning and environmental sustainability. By emphasizing both the practical applications and theoretical contributions, this research underscores the significance of community involvement and forward-thinking strategies in shaping the future of urban landscapes. As cities evolve, incorporating these insights into planning and development practices will create resilient and harmonious urban environments.

Conclusion Outline for Research Paper

This outline for a research paper conclusion provides a structured framework to ensure that your ending effectively summarizes the key elements of your research paper and leaves a lasting impression on your readers. Adjust the content based on the specific requirements and focus of your research.

Restate the Thesis Statement

• Briefly restate the main thesis or research question.
• Emphasize the core objective or purpose of the study.

Summarize Key Findings

• Recap the main points and key findings from each section of the paper.
• Provide a concise overview of the research journey.

Discuss Implications

• Explore the broader implications of the research findings.
• Discuss how the results contribute to the existing body of knowledge in the field.

Address Limitations

• Acknowledge any limitations or constraints encountered during the research process.
• Explain how these limitations may impact the interpretation of the findings.

Suggest Areas for Future Research

• Propose potential directions for future studies related to the topic.
• Identify gaps in the current research that warrant further exploration.

Reaffirm Significance

• Reaffirm the importance and relevance of the research in the broader context.
• Highlight the practical applications or real-world implications of the study.

Concluding Statement

• Craft a strong, memorable closing statement that leaves a lasting impression.
• Sum up the overall impact of the research and its potential contribution to the field.

Study the full guide on how to make a research paper outline here, which will also specify the conclusion writing specifics to improve your general prowess.

Tips on How to Make a Conclusion in Research

Here are key considerations regarding a conclusion for research paper to not only recap the primary ideas in your work but also delve deeper to earn a higher grade:

• Provide a concise recap of your main research outcomes.
• Remind readers of your research goals and their accomplishments.
• Stick to summarizing existing content; refrain from adding new details.
• Emphasize why your research matters and its broader implications.
• Clearly explain the practical or theoretical impact of your findings.
• Prompt readers to reflect on how your research influences their perspective.
• Briefly discuss the robustness of your research methods.
• End with a suggestion for future research or a practical application.
• Transparently address any constraints or biases in your study.
• End on a powerful note, leaving a memorable impression on your readers.

For your inspiration, we’ve also prepared this research proposal example APA , which dwells on another important aspect of research writing.

How to Write a Research Paper Conclusion

As you finish your research paper, the conclusion takes center stage. In this section, we've got five practical tips for writing a conclusion for a research paper. We'll guide you through summarizing your key findings, revisiting your research goals, discussing the bigger picture, addressing any limitations, and ending on a powerful note. Think of it as your roadmap to creating a conclusion that not only wraps up your research but also leaves a lasting impact on your readers. Let's dive in and make sure your conclusion stands out for all the right reasons!

Synthesize Core Discoveries. Initiate your conclusion by synthesizing the essential discoveries of your research. Offer a succinct recapitulation of the primary points and outcomes you have elucidated in your paper. This aids in reinforcing the gravity of your work and reiterates the pivotal information you have presented.

Revisit Research Objectives. Revisit the research objectives or questions you outlined at the beginning of your paper. Assess whether you have successfully addressed these objectives and if your findings align with the initial goals of your research. This reflection helps tie your conclusion back to the purpose of your study.

Discuss Implications and Contributions. Discuss the broader implications of your research and its potential contributions to the field. Consider how your findings might impact future research, applications, or understanding of the subject matter. This demonstrates the significance of your work and places it within a larger context.

Address Limitations and Future Research. Acknowledge any limitations in your study, such as constraints in data collection or potential biases. Briefly discuss how these limitations might have affected your results. Additionally, suggest areas for future research that could build upon your work, addressing any unanswered questions or unexplored aspects. This demonstrates a thoughtful approach to your research.

End with a Strong Conclusion Statement. Conclude your research paper with a strong and memorable statement that reinforces the key message you want readers to take away. This could be a call to action, a proposal for further investigation, or a reflection on the broader significance of your findings. Leave your readers with a lasting impression that emphasizes the importance of your research. Remember that you can buy a research paper anytime if you lack time or get stuck in writer’s block.

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Stylistic Devices to Use in a Conclusion

Discover distinctive stylistic insights that you can apply when writing a conclusion for a research paper:

• Rhetorical Questions. When using rhetorical questions, strategically place them to engage readers' minds. For instance, you might pose a question that prompts reflection on the broader implications of your findings, leaving your audience with something to ponder.
• Powerful Language. Incorporate strong language to convey a sense of conviction and importance. Choose words that resonate with the overall tone of your research and amplify the significance of your conclusions. This adds weight to your key messages.
• Repetitions. Repetitions can be employed to reinforce essential ideas. Reiterate key phrases or concepts in a way that emphasizes their importance without sounding redundant. This technique serves to drive home your main points.
• Anecdotes. Integrating anecdotes into your conclusion can provide a human touch. Share a brief and relevant story that connects with your research, making the information more relatable and memorable for your audience.
• Vivid Imagery. Lastly, use vivid imagery to paint a picture in the minds of your readers. Appeal to their senses by describing scenarios or outcomes related to your research. This creates a more immersive and lasting impression.

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How to Make a Conclusion Logically Appealing

Knowing how to write a conclusion for a research paper that is logically appealing is important for leaving a lasting impression on your readers. Here are some tips to achieve this:

Logical Sequencing

• Present your conclusion in a structured manner, following the natural flow of your paper. Readers should effortlessly follow your thought process, making your conclusion more accessible and persuasive.

Reinforce Main Arguments

• Emphasize the core arguments and findings from your research. By reinforcing key points, you solidify your stance and provide a logical culmination to your paper.

Address Counterarguments

• Acknowledge and address potential counterarguments or limitations in your research. Demonstrate intellectual honesty and strengthen your conclusion by preemptively addressing potential doubts.

Connect with Introduction

• Revisit themes or concepts introduced in your introduction to create a cohesive narrative, allowing readers to trace the logical progression of your research from start to finish.

Propose Actionable Insights

• Suggest practical applications or recommendations based on your findings. This will add a forward-looking dimension, making your conclusion more relevant and compelling.

Highlight Significance

• Clearly articulate the broader implications of your research to convey the importance of your work and its potential impact on the field, making your conclusion logically compelling.

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Avoid These Things When Writing a Research Paper Conclusion

As you write your conclusion of research paper, there’s a list of things professional writers don’t recommend doing. Consider these issues carefully:

• Repetition of Exact Phrases
• Repetitively using the same phrases or sentences from the main body. Repetition can make your conclusion seem redundant and less engaging.
• Overly Lengthy Summaries
• Providing excessively detailed summaries of each section of your paper. Readers may lose interest if the conclusion becomes too long and detailed.
• Unclear Connection to the Introduction
• Failing to connect the conclusion back to the introduction. A lack of continuity may make the paper feel disjointed.
• Adding New Arguments or Ideas
• Introducing new arguments or ideas that were not addressed in the body. This can confuse the reader and disrupt the coherence of your paper.
• Overuse of Complex Jargon
• Using excessively complex or technical language without clarification. Clear communication is essential in the conclusion, ensuring broad understanding.
• Apologizing or Undermining Confidence
• Apologizing for limitations or expressing doubt about your work. Maintain a confident tone; if limitations exist, present them objectively without undermining your research.
• Sweeping Generalizations
• Making overly broad or unsupported generalizations. Such statements can weaken the credibility of your conclusion.
• Neglecting the Significance
• Failing to emphasize the broader significance of your research. Readers need to understand why your findings matter in a larger context.
• Abrupt Endings
• Concluding abruptly without a strong closing statement. A powerful ending leaves a lasting impression; avoid a sudden or weak conclusion.

Research Paper Conclusion Example

That covers the essential aspects of summarizing a research paper. The only remaining step is to review the conclusion examples for research paper provided by our team.

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Final Thoughts

In conclusion, the knowledge of how to write the conclusion of a research paper is pivotal for presenting your findings and leaving a lasting impression on your readers. By summarizing the key points, reiterating the significance of your research, and offering avenues for future exploration, you can create a conclusion that not only reinforces the value of your study but also encourages further academic discourse. Remember to balance brevity and completeness, ensuring your conclusion is concise yet comprehensive. Emphasizing the practical implications of your research and connecting it to the broader academic landscape will help solidify the impact of your work. Pay someone to write a research paper if you are having a hard time finishing your coursework on time.

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How To Write A Conclusion For A Research Paper?

What should the conclusion of a research paper contain, how to start a conclusion paragraph for a research paper.

Daniel Parker

is a seasoned educational writer focusing on scholarship guidance, research papers, and various forms of academic essays including reflective and narrative essays. His expertise also extends to detailed case studies. A scholar with a background in English Literature and Education, Daniel’s work on EssayPro blog aims to support students in achieving academic excellence and securing scholarships. His hobbies include reading classic literature and participating in academic forums.

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How to Write a Good Conclusion Paragraph (+30 Examples)

A good conclusion paragraph is the lasting impression you want to leave with your reader.

Here is a quick summary of how to write a good conclusion paragraph:

Write a good conclusion paragraph by summarizing key points, restating your thesis, and providing a final thought or call to action. Ensure it wraps up your main ideas, reinforces your argument, and leaves the reader with something to ponder.

This ultimate guide will walk you through the steps to craft an effective conclusion, along with 30 examples to inspire you.

5 Steps for Writing a Good Conclusion Paragraph

Table of Contents

There are five main steps to writing a good conclusion.

Let’s go through each step

1. Understand the Purpose

The conclusion is your final opportunity to leave an impact.

It should tie together your main ideas, reinforce your message, and give the reader a sense of closure.

Wrap Up Your Main Ideas

The conclusion should succinctly wrap up the main points of your writing. Think of it as a summary that captures the essence of your arguments without going into detailed explanations.

This helps reinforce what you have discussed and ensures that the reader remembers the core message.

Reinforce Your Thesis

Your thesis statement is the foundation of your writing.

In the conclusion, restate it in a new way to reinforce your central argument. This reminds the reader of the purpose of your writing and underscores its significance.

Give a Sense of Closure

A good conclusion gives a sense of closure to the reader. It signals that the discussion has come to an end and that all points have been addressed. This helps the reader feel that the piece is complete and that their time was well-spent.

Leave the Reader with Something to Think About

The best conclusions go beyond merely summarizing the content.

They leave the reader with a final thought or reflection that stays with them. This could be a call to action, a prediction about the future, or a thought-provoking question that encourages further reflection on the topic.

2. Summarize Key Points

Briefly summarize the key points discussed in the body of your text.

Avoid introducing new information. This helps the reader recall the main ideas.

Brief Summary

The summary should be concise and to the point. Highlight the main ideas discussed in your writing without going into detailed explanations. This helps refresh the reader’s memory of your key points.

Avoid New Information

Introducing new information in the conclusion can confuse the reader. The conclusion is not the place to present new arguments or data. Stick to summarizing what has already been discussed.

Recall Main Ideas

Summarizing the key points helps the reader recall the main ideas of your writing. This reinforces the message and ensures that the reader takes away the most important information from your piece.

“In conclusion, adopting sustainable practices, reducing waste, and promoting renewable energy are essential steps towards a greener future.”

3. Restate the Thesis

Restate your thesis in a new way. This reinforces your argument without sounding repetitive.

Restate, Don’t Repeat

Restating the thesis means expressing it in a new way.

Avoid repeating it verbatim.

Instead, rephrase it to reinforce your argument and show that you have successfully argued your point throughout the piece.

Reinforce the Argument

Restating the thesis helps reinforce your central argument. It reminds the reader of the purpose of your writing and underscores its significance.

Provide Closure Restating the thesis in the conclusion gives a sense of closure.

It signals that the discussion has come full circle and that you have addressed your initial argument.

“By implementing these strategies, we can significantly reduce our carbon footprint and protect our planet for future generations.”

4. Provide a Final Thought

Offer a final thought or reflection to leave a lasting impression. This could be a call to action, a prediction, or a thought-provoking question.

Final Thought or Reflection

A final thought or reflection can leave a lasting impression on the reader.

It shows that you are not just summarizing your points but also offering a deeper insight or perspective.

Call to Action

A call to action encourages the reader to take the next step.

It motivates them to act based on the information or arguments presented in your writing.

Prediction or Question

A prediction about the future or a thought-provoking question can engage the reader and encourage further reflection. This leaves the reader with something to think about even after they have finished reading.

“As we move forward, it’s crucial to remember that every small effort counts. Together, we can make a difference.”

5. Use a Call to Action (if applicable)

If your piece is meant to persuade or encourage action, include a call to action. This motivates the reader to take the next step.

Motivate the Reader

A call to action motivates the reader to take the next step.

It encourages them to act based on the information or arguments presented in your writing.

Encourage Action

Including a call to action is especially important in persuasive writing. It encourages the reader to act on the information provided and make a change or take a specific action.

Provide Clear Steps

A good call to action provides clear steps for the reader to follow.

It should be specific and actionable, guiding the reader on what to do next.

“Join us in making a positive change. Start today by reducing your plastic use and spreading awareness about environmental conservation.”

Check out this video about how to write a good conclusion:

How to Write a Good Conclusion for an Essay

Writing a good conclusion for an essay involves summarizing your main points, restating your thesis, and providing a final thought or reflection.

Here’s how:

• Summarize Main Points : Briefly recap the key points discussed in the body of your essay.
• Restate Thesis : Paraphrase your thesis statement to reinforce your argument.
• Final Thought : Offer a final insight, question, or call to action to leave a lasting impression.

This approach ensures your essay feels complete and leaves the reader with a clear understanding of your argument.

How to Write a Good Conclusion for an Argumentative Essay

A strong conclusion for an argumentative essay should not only summarize the main points and restate the thesis but also emphasize the importance of your argument.

Follow these steps:

• Summarize Arguments : Briefly outline the main arguments presented.
• Restate Thesis : Rephrase your thesis to highlight its significance.
• Address Counterarguments : Acknowledge opposing viewpoints and reinforce why your argument is stronger.
• Call to Action : Encourage the reader to take action or reconsider their position.

How to Write a Good Conclusion for a Research Paper

Crafting a good conclusion for a research paper involves summarizing your findings, discussing their implications, and suggesting future research.

Here’s a guide:

• Summarize Findings : Recap the key results of your research.
• Discuss Implications : Explain the significance of your findings and how they contribute to the field.
• Restate Research Question : Reiterate the research question and how your findings address it.
• Suggest Future Research : Propose areas for further investigation.

This format provides a comprehensive and thoughtful conclusion that underscores the importance of your research and its potential impact.

30 Examples of Good Conclusion Paragraphs

Let’s explore some good examples of good conclusions.

Example 1: Environmental Essay

“In conclusion, the preservation of our natural resources is not just a necessity but a responsibility we owe to future generations. By taking small steps today, we can ensure a healthier planet tomorrow.”

Example 2: Technology Article

“As we embrace the advancements in technology, it is vital to remain vigilant about privacy and security. Staying informed and proactive can help us navigate the digital landscape safely.”

Example 3: Health and Wellness Blog

“Ultimately, achieving a balanced lifestyle requires dedication and mindfulness. By prioritizing our well-being, we can lead healthier and more fulfilling lives.”

Example 4: Business Report

“In summary, the market analysis indicates a positive trend for our product. With strategic planning and execution, we can capitalize on these opportunities and drive growth.”

Example 5: Education Essay

“In the end, fostering a love for learning in students is the key to their success. By creating engaging and supportive educational environments, we can inspire the next generation of leaders.”

Example 6: Travel Blog

“To conclude, exploring new destinations enriches our lives and broadens our perspectives. Embrace the adventure and discover the beauty of our world.”

Example 7: Personal Development Article

“In the final analysis, personal growth is a lifelong journey. Embrace challenges, learn from experiences, and continue striving to become the best version of yourself.”

Example 8: Marketing Case Study

“In closing, the data clearly shows that targeted marketing strategies significantly improve customer engagement and sales. By refining our approach, we can achieve even greater success.”

Example 9: Historical Analysis

“In conclusion, the events of the past continue to shape our present and future. Understanding history is essential to making informed decisions and avoiding past mistakes.”

Example 10: Scientific Research Paper

“Ultimately, the findings of this study contribute to our understanding of the subject and open the door for further research. Continued exploration in this field is vital for advancing knowledge.”

Example 11: Political Commentary

“In the end, civic engagement is crucial for a functioning democracy. Stay informed, participate in discussions, and exercise your right to vote.”

Example 12: Fashion Blog

“To wrap up, fashion is a powerful form of self-expression. Embrace your unique style and let your wardrobe reflect your personality.”

Example 13: Food Blog

“In conclusion, cooking at home not only saves money but also allows you to experiment with flavors and ingredients. Start your culinary journey today and discover the joys of homemade meals.”

Example 14: Sports Article

“Ultimately, teamwork and perseverance are the foundations of success in sports. Keep pushing your limits and strive for excellence on and off the field.”

Example 15: Literature Analysis

“In summary, the themes explored in this novel resonate with readers and offer valuable insights into the human condition. Its timeless message continues to inspire and provoke thought.”

Example 16: Parenting Blog

“In the end, raising children requires patience, love, and commitment. Cherish the moments, and remember that every effort you make shapes their future.”

Example 17: Finance Article

“To conclude, financial planning is essential for securing your future. Start today by setting clear goals and creating a budget that aligns with your aspirations.”

Example 18: Career Advice Blog

“In conclusion, building a successful career takes time and dedication. Stay focused, seek opportunities for growth, and never stop learning.”

Example 19: Fitness Blog

“Ultimately, regular exercise and a balanced diet are key to maintaining a healthy lifestyle. Stay motivated, and remember that every step counts towards your fitness goals.”

Example 20: DIY Blog

“In summary, DIY projects are a rewarding way to personalize your space and learn new skills. Get creative and start your next project today.”

Example 21: Relationship Advice

“In the end, strong relationships are built on communication, trust, and mutual respect. Nurture your connections and strive for harmony in your interactions.”

Example 22: Pet Care Blog

“To wrap up, responsible pet ownership involves understanding your pet’s needs and providing them with a loving home. Invest in their well-being, and they’ll reward you with unconditional love.”

Example 23: Environmental Science Paper

“In conclusion, addressing climate change requires global cooperation and immediate action. Every effort counts, and together we can create a sustainable future.”

Example 24: Technology Review

“Ultimately, this gadget offers impressive features that enhance convenience and efficiency. Consider it for your next tech upgrade.”

Example 25: Psychology Article

“In summary, understanding human behavior is crucial for improving mental health and well-being. Continue exploring this fascinating field for more insights.”

Example 26: Gardening Blog

“In the end, gardening is a therapeutic and rewarding hobby that connects us with nature. Start your garden today and enjoy the benefits of fresh produce and beautiful blooms.”

Example 27: Home Improvement Article

“To conclude, home improvement projects can significantly enhance your living space and increase property value. Plan carefully and enjoy the transformation.”

Example 28: Social Media Marketing

“In conclusion, effective social media marketing requires consistency, creativity, and engagement. Develop a strategy that resonates with your audience and watch your brand grow.”

Example 29: Automotive Review

“Ultimately, this vehicle combines performance, style, and safety. Take it for a test drive and experience its capabilities firsthand.”

Example 30: Music Blog

“In summary, music has the power to evoke emotions and bring people together. Explore different genres and find the soundtrack to your life.”

Tips for Writing a Strong Conclusion

Here are some simple but good tips for writing a powerful conclusion:

• Keep it Concise – A good conclusion should be short and to the point. Avoid unnecessary details and focus on wrapping up your main ideas.
• Use Clear Language – Ensure your language is clear and easy to understand. Avoid jargon and complex sentences.
• Be Consistent – Maintain the same tone and style as the rest of your text. Consistency helps create a seamless reading experience.
• End on a Positive Note – Whenever possible, end with a positive or uplifting message. This leaves the reader with a good impression.

Common Mistakes to Avoid

There are some common mistakes that many writers make when crafting their conclusions.

• Introducing New Information – Don’t introduce new ideas or arguments in the conclusion. This can confuse the reader and dilute your main points.
• Being Vague – Avoid vague statements that don’t add value. Be specific and clear in your summary.
• Repetitiveness – Don’t repeat the same points over and over. Restate your thesis and key points in a new way.
• Ignoring the Thesis – Make sure to tie your conclusion back to your thesis. This reinforces your argument and gives a sense of closure.

Final Thoughts: How to Write a Good Conclusion Paragraph

Writing a good conclusion paragraph is essential for creating a cohesive and impactful piece of writing.

By summarizing key points, restating the thesis, providing a final thought, and using a call to action, you can craft a strong conclusion that leaves a lasting impression.

Use the 30 examples provided to inspire your own writing and ensure your conclusions are always effective and engaging.

Read This Next:

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• Types of Evidence in Writing [Ultimate Guide + Examples]
• Narrative Writing Graphic Organizer [Guide + Free Templates]
• How to Write a Hook (40 Good Examples)

• USC Libraries
• Research Guides

Organizing Your Social Sciences Research Paper

• Broadening a Topic Idea
• Purpose of Guide
• Design Flaws to Avoid
• Independent and Dependent Variables
• Glossary of Research Terms
• Reading Research Effectively
• Narrowing a Topic Idea
• Extending the Timeliness of a Topic Idea
• Academic Writing Style
• Applying Critical Thinking
• Choosing a Title
• Making an Outline
• Paragraph Development
• Research Process Video Series
• Executive Summary
• The C.A.R.S. Model
• Background Information
• The Research Problem/Question
• Theoretical Framework
• Citation Tracking
• Content Alert Services
• Evaluating Sources
• Primary Sources
• Secondary Sources
• Tiertiary Sources
• Scholarly vs. Popular Publications
• Qualitative Methods
• Quantitative Methods
• Insiderness
• Using Non-Textual Elements
• Limitations of the Study
• Common Grammar Mistakes
• Writing Concisely
• Avoiding Plagiarism
• Footnotes or Endnotes?
• Further Readings
• Generative AI and Writing
• USC Libraries Tutorials and Other Guides
• Bibliography

Importance of Broadening the Research Topic

It is important to adopt a flexible approach when choosing a topic to investigate. The goal when writing any paper is to choose a research problem that is focused and time-limited. However, your starting point should not be so narrowly defined that you unnecessarily constrict your opportunity to investigate the topic thoroughly. A research problem that is too narrowly defined leads to any of the following problems :

• You can't find enough information and what you do find is tangential or irrelevant.
• You find information that is so specific that it can't lead to any significant conclusions.
• Your sources cover so few ideas that you can't expand them into a significant paper.
• The research problem is so case specific that it limits opportunities to generalize or apply the results to other contexts.
• The significance of the research problem is limited to only a very small, unique population.

Ravitch, Sharon M. and Matthew Riggan. Reason and Rigor: How Conceptual Frameworks Guide Research . Los Angeles, CA: SAGE, 2017.

Strategies for Broadening the Research Topic

In general, an indication that a research problem is too narrowly defined is that you can't find any relevant or meaningful information about it. If this happens, don't immediately abandon your efforts to investigate the problem because it could very well be an excellent topic of study. A good way to begin is to look for parallels and opportunities for broader associations that apply to the initial research problem. A strategy for doing this is to ask yourself the basic six questions of who, what, where, when, how, and why.

Here is an example of how to apply the six questions strategy to broadening your topic. Let's use the research topic of how to investigate ways to improve trade relations between Peru and Bolivia as an example. Ask yourself:

• Who? -- are there other countries involved in the relations between these two countries that might want to challenge or encourage this relationship? Are there particular individuals or special interest groups [e.g., politicians, union leaders, etc.] promoting trade relations or trying to inhibit it? [remember to ask either the individual who question, the collective who question, or the institutional who question].
• What? -- what are the specific trading commodities you are examining? Are there commodities not currently traded between Peru and Bolivia that could be? What commodities are being traded but should be traded in greater volume? What barriers exist that may help or hinder the import-exports of specific commodities?
• Where? -- where are examples of other bi-lateral trade agreements that could model the potential for closer trade relations between Peru and Bolivia? Where are the benefits most likely to be felt within each country? Note that the question of where can also relate to specific spatial and geographical issues, such as, are there any areas impeding transportation of goods in the region?
• When? -- how long have these countries had or not had trade relations? How far into the future might a trade relationship last given other factors? The question of when can apply to either past issues or future areas of interest.
• How? -- how might Peru and Bolivia forge these ties in relation to, for example, long-standing internal conflicts within each country? Note that the how question can also be framed as, "In what way might...." [e.g., In what way might improved trade relations lead to other forms of economic exchanges between the two countries?].
• Why? -- what advantages can each country gain by pursuing active trade relations? Why might other countries be concerned about closer ties between these two countries? Asking why can illuminate the " So What? " question applied to your topic and, thus, provide a means of assessing significance.

Reflecting upon these six questions during your initial review of the literature can help you formulate ways to expand the parameters of your initial research problem, providing an opportunity to identify new avenues of investigation and centering your study around gaps in the literature when answers to questions cannot be found. Once you've identified additional directions in which to proceed with your topic, you can try narrowing it down again, if needed.

NOTE:   Do not determine on your own that a research problem is too narrowly defined . Always consult with a librarian before making this assumption because librarians are experts in finding information and interpreting it in relation to a research problem. As such, they can help guide you to undiscovered research or suggest ways to design a broader analysis of your research problem using resources you did not even know existed.

Booth, Wayne C. The Craft of Research . Fourth edition. Chicago, IL: The University of Chicago Press, 2016; Coming Up With Your Topic. Institute for Writing Rhetoric. Dartmouth College; Getting Started With Your Research: A Self-Help Guide to Quality Information, Jean and Alexander Heard Library. Vanderbilt University; Strategies for Broadening a Topic. University Libraries. Information Skills Modules. Virginia Tech University.

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• Last Updated: May 25, 2024 4:09 PM
• URL: https://libguides.usc.edu/writingguide

Clinical Trials Data Management and Analysis

Medical research is a process of gathering data that will expand scientists' understanding of human health. Researchers take steps to ensure the accuracy of all their data, then use sophisticated methods to analyze their findings to ensure the accuracy of their conclusions.

Table of Contents:

How Researchers Use Biostatistics to Analyze Data

How researchers protect data integrity during clinical trials, how researchers use real-world evidence in clinical studies, continuing data collection after clinical trials, learn more about clinical trials.

Putting together a medical research study is no simple task. Scientists must create a detailed study design that lays out every aspect of the research. This careful process allows the research team to have a clear plan for gathering and using all the data for their research.

Clinical trial data management is one of the biggest priorities in research. Scientists must ensure that study participants understand what the team is trying to learn and what information they will need in the process. Researchers must accurately record data and analyze it carefully to ensure their findings are correct. This requires multiple data management techniques.

Biostatistics is a branch of statistics that deals with data about living organisms. Statisticians analyze data related to humans, animals, and plants to identify patterns. These patterns can be used to assess important scientific information. Biostatistics can also be used to predict health risks in certain groups and give doctors an idea of how different health conditions progress under different circumstances.

In research, biostatistics and clinical data analysis are essential parts of study design and analysis at all phases. Researchers can also use biostatistics when designing a new study. Data from past studies can be used for modeling, pre-study simulations, and feasibility analysis. Preclinical modeling can be used during clinical trials to adapt the study design if needed. Once the study is complete, biostatistical analysis is a key component in writing reports about the study findings.

Good science requires good data and good clinical data management. Researchers need to ensure that the information they collect is correct and obtained appropriately. One key step in ensuring data integrity is getting informed consent from study participants. Participants must knowingly agree to all research activities, with sufficient understanding of the potential consequences. Data acquired without appropriate informed consent casts doubt on the study's overall validity.

Once researchers have proper informed consent , all data gathered in the study must be valid, complete, and well-documented. The goal of data gathering and storage is to ensure that the collected information can be used to reconstruct the study and confirm the findings.

Data protection is another aspect of data management. Researchers need to protect participant privacy . They need to have adequate security tools to make sure all data is protected and participants' identities are concealed .

Quality assurance is the process of checking data and data collection methods throughout the trial. This can be done by the research team or quality management experts at the facility where the research is taking place. Government regulators may also conduct audits to ensure all the methods and findings are appropriate and follow best practices.

Real-world evidence is data collected outside the parameters of a study. It can offer valuable insight into how certain behaviors, health conditions, or treatments affect people daily without the rules or oversight imposed by a clinical trial. Real-world data can also offer insights into how particular conditions or treatments affect people over different periods.

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Real-world evidence can help with designing new clinical trials. The data can be used as a biostatistic to model the potential outcomes of the trial. In some cases, real-world data can replace the placebo arm of a study. Researchers can administer the treatment to all participants and compare study outcomes to real-world data instead of monitoring a control group of participants who receive the placebo instead of treatment.

Data gathering and clinical data analysis continue after a successful study is completed and a new treatment has been approved. Clinical trials are one way of determining a treatment's effectiveness, but they cannot predict all the possible outcomes when people start using the treatment outside the study.

Both researchers and regulatory agencies collect information about how the treatment affects people. This allows researchers to understand the long-term effects of new treatments. It also ensures that regulators identify any unexpected safety issues and take steps to protect people from harm.

Post-market data gathering and management may involve patient reporting systems where people can send information about the adverse effects of treatments to the FDA . Researchers may arrange post-study follow-ups with participants to gather more information about their outcomes over the long term. Researchers may also use real-world data from insurance companies or healthcare systems to understand better how the treatment affects people. This post-market data is another set of biostatistics that can be used to assess current and future research.

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Qaleh Kurd Cave (Qazvin, Iran): Oldest Evidence of Middle Pleistocene Hominin Occupations and a Human Deciduous Tooth in the Iranian Central Plateau

• Published: 23 May 2024
• Volume 7 , article number  16 , ( 2024 )

Cite this article

• Hamed Vahdati Nasab 1 , 2   na1 ,
• Gilles Berillon 2   na1 ,
• Seyyed Milad Hashemi 1 , 2 ,
• Jean-Jacques Bahain 15 ,
• Noémie Sévêque 3 ,
• Mozhgan Jayez 4 ,
• Stéphanie Bonilauri 2 ,
• Guillaume Jamet 5 , 6 ,
• Mohammad Akhavan Kharazian 2 , 6 , 12 , 13 ,
• Asghar Nateghi 7 ,
• Alieh Abdollahi 7 ,
• Pierre Antoine 6 ,
• Iraj Beheshti 8 ,
• Nicolas Boulbes 2 , 14 ,
• Cécile Chapon-Sao 2 ,
• Xavier Gallet 2 ,
• Christophe Falguères 2 ,
• Lisa Garbé 2 ,
• Mandan Kazzazi 9 ,
• Ahmad Zavar Mousavi 10 ,
• Sareh Nematollahinia 1 ,
• Jonathan Özçelebi 2 ,
• Emmanuelle Stoetzel 2 ,
• Olivier Tombret 2 &
• Valéry Zeitoun 11  

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The Iranian Central Plateau (ICP) with the Alborz and the Zagros Mountains is located at the crossroads between the Levant and the Caucasus to the west and Central Asia and East Asia to the east. These two regions yielded key paleoanthropological and archaeological sites from the Middle Pleistocene period. These discoveries highlight a large human biological and cultural diversity in this area during the Middle Pleistocene and raise questions about the interactions these humans had. Yet, despite decades of field research, no Middle Pleistocene assemblage in a clear chronological and stratigraphic context was known in the ICP, the Zagros, and the Alborz Mountains that could contribute to this debate; so far, the earliest of the area is dated of 80 ka. The Joint Iranian and French Paleoanthropological Project reinvestigated the cave of Qaleh Kurd (Qazvin). The Qaleh Kurd cave is located at 2137 m asl at the very western limit of the ICP, at its boundary with the Zagros Mountains. Here, we report on the discovery of in situ Middle Pleistocene archaeological assemblages, including a human deciduous first upper molar associated with a rich lithic and faunal material, and a first description of the chrono-stratigraphic framework of the deposits. The excavation and the archaeological and geoarchaeological analyses show that humans occupied the site during the Middle Pleistocene, during a period ranging from ca 452 ± 32 and 165 ± 11 ka. This chronology pushes back the earliest dated evidence of human settlement in the ICP by more than 300 ka. The human deciduous first upper molar comes from the upper part of the Middle Pleistocene sequence. The crown of the tooth is widely impacted by wear and carries that limit taxonomic inferences. The study of the three upper archaeological assemblages shows that the cave was recurrently occupied by humans of early Middle Paleolithic cultures. These assemblages recall some traits of sub-contemporary assemblages known in the Caucasus and the Levant but also the later Middle Paleolithic of the Zagros. The faunal assemblage is mainly composed of horse remains. The remains are very fragmented and show numerous anthropogenic stigmata that indicate significant butchery activities on site. From a large regional and chronological perspective, these findings make Qaleh Kurd Cave a key site for the knowledge of early human settlements and dispersals between the Levant and Asia.

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Data availability.

No data outside the submitted manuscript file. Data and materials may made available on demand to first authors; archaeological materials being under the care of the cultural heritage service of the Qazvin Province.

The ICP is the large area surrounded by the Zagros Mountains to the west, the Alborz Mountains in the north, the Kopet Dagh Mountains in the east, and the central Iranian block (mainly the Lut Desert) in the south.

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Acknowledgements

Our work on Qaleh Kurd cave was made possible thanks to the financial support of the Regional Service of Cultural Heritage of the Province of Qazvin, the Iranian Center for Archaeological Research (ICAR), the Ministry of Europe and Foreign Affairs of France (Commission des Fouilles archéologiques à l'étranger), Tarbiat Modares University, the French Embassy in Iran, and the UMR7194 CNRS-MNHN-UPVD. We would like to express our deepest gratitude to them for their support and trust in our team. We would like to thank Dr. Sadjad Alibaigi for his generous allowance to work on this magnificent site. We would also like to express our gratitude to the Iranian Ministry of Cultural Heritage and Tourism, in particular Drs. Rouhollah Shirazi, Kourosh Roustaei, and Leyla Khosravi, directors of the Iranian Center for Archaeological Research (ICAR), at the time of our excavations, for their collaboration in the preparation of our missions and for allowing us to work in the field. We would like to thank Mrs. Solgi and her colleagues at the Tehran University Medical Science Preclinical Core Facility for providing a high-resolution micro-CT scan of the Qaleh Kurd tooth. We also thank Mr. Hazratiha, Director of the Cultural Heritage Office of Qazvin Province at the time of the first mission in 2018; Mr. Khazaeli the current director; and Mrs. Mohammadi, Mr. Asgari, Fanaee, and their Delegate for Archaeology, for their hospitality and logistical support in the field of Qaleh Kurd. We are thankful to Dr. Sébastein Nomade for his assistance in the preparation of 14C samples as well as to Dr. M. Alirezazadeh for his assistance in producing the map used in Fig. 1 . Obviously, the fieldwork was not possible without the tremendous job of the crew, which their names were not included in the author list: in alphabetical order, L. Alinia, M. Alirezazadeh, M. Etminan, T. Izadyari, Z. Kamrani, S. Ganji, A. Khanian, D. Mahmoudi, S. Nazif, S. Shafiee, M.J. Shoaee. We would like to thank Shannon McPherron, editor, as well as Tobias Lauer and other anonymous reviewers for their helpful comments on a previous version of the manuscript.

The Regional Service of Cultural Heritage of the Province of Qazvin for financial support of the field campaigns

The Iranian Center for Archaeological Research (ICAR) for financial support of the field campaigns

A grant from the Ministry of Europe and Foreign Affairs of France (Commission des Fouilles archéologiques à l'étranger) for financial support of the field campaigns and laboratory analyses

Tarbiat Modares University for financial support of the laboratory analyses

UMR7194 CNRS-MNHN-UPVD for financial support of the laboratory analyses. The ESR spectrometer, Q-ICP-mass spectrometer and portable gamma spectrometer of the Muséum National d’Histoire Naturelle used for part of the analyses were bought with the financial support of the Région Île-de-France’ (for the two first devices) and Région Centre respectively.

The geoarchaeological analysis has been done in the frame of a doctoral scholarship (M.A. Kharazian) granted by the French Embassy in Iran.

Author information

Hamed Vahdati Nasab and Gilles Berillon are both first co-authors, equally contributing to the research design and the preparation of the manuscript.

Authors and Affiliations

Department of Archaeology, Tarbiat Modares University, Tehran, Iran

Hamed Vahdati Nasab, Seyyed Milad Hashemi & Sareh Nematollahinia

UMR7194 CNRS-MNHN-UPVD/Département Homme et Environnement, Musée de l’Homme—Palais de Chaillot, Paris, France

Hamed Vahdati Nasab, Gilles Berillon, Seyyed Milad Hashemi, Stéphanie Bonilauri, Mohammad Akhavan Kharazian, Nicolas Boulbes, Cécile Chapon-Sao, Xavier Gallet, Christophe Falguères, Lisa Garbé, Jonathan Özçelebi, Emmanuelle Stoetzel & Olivier Tombret

UMR7044 ArcHiMèdE, Strasbourg, France

Noémie Sévêque

Department of Archaeology, University of Tehran, Tehran, Iran

Mozhgan Jayez

INRAP, Department Grand Ouest, Paris, France

Guillaume Jamet

UM8591 CNRS/Université Paris 1/UPEC, Laboratoire de Géographie Physique, Environnements Quaternaires et Actuels, Thiais, France

Guillaume Jamet, Mohammad Akhavan Kharazian & Pierre Antoine

Department of Archaeology, Islamic Azad University, Tehran, Iran

Asghar Nateghi & Alieh Abdollahi

Center for Conservation and Restoration Research, Research Institute of Cultural Heritage and Tourism (RICHT), Tehran, Iran

Iraj Beheshti

Sustainable Computing Lab, Vienna University of Economy and Business (Wirtschaftsuniversität Wien WU), Wien, Austria

Mandan Kazzazi

Department of Archaeology, Marlik Institute for Higher Education, Nowshahr, Iran

Ahmad Zavar Mousavi

Centre de Recherche en Paléontologie-Paris CR2P UMR7207 MNHN-SU-CNRS, Paris, France

Valéry Zeitoun

School of Geography, Earth and Atmospheric Sciences, University of Melbourne, Victoria, Australia

Mohammad Akhavan Kharazian

Department of Geography, School of Environment, Education and Development, University of Manchester, Manchester, UK

EPCC, Centre Européen de Recherches Préhistoriques de Tautavel, Tautavel, France

Nicolas Boulbes

UMR7194 CNRS-MNHN-UPVD / Département Homme et Environnement, Institut de Paléontologie Humaine, Paris, France

Jean-Jacques Bahain

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Contributions

Hamed Vahdati Nasab: head of the mission, data gathering, data analysis, writing the manuscript. Gilles Berillon: head of the mission, data gathering, data analysis, writing the manuscript. Seyyed Milad Hashemi: data gathering, data analysis, writing the manuscript. Jean-Jacques Bahain: data analysis, writing the manuscript. Noémie Sévêque: data gathering, data analysis, writing the manuscript. Mozhgan Jayez: data gathering, data analysis, writing the manuscript. Stéphanie Bonilauri: data gathering, data analysis, writing the manuscript. Guillaume Jamet: data gathering, data analysis, writing the manuscript. Mohammad Akhavan Kharazian: data gathering, data analysis, writing the manuscript. Asghar Nateghi: data gathering. Alieh Abdollahi: data gathering. Pierre Antoine: data analysis. Iraj Beheshti: data analysis. Nicolas Boulbes: data analysis, writing the manuscript. Cécile Chapon-Sao: data analysis. Xavier Gallet: data analysis. Christophe Falguères: data analysis. Lisa Garbé: data analysis. Mandan Kazzazi: data analysis. Ahmad Zavar Mousavi: data gathering. Sareh Nematollahinia: data analysis, data gathering. Jonathan Özçelebi: data analysis. Emmanuelle Stoetzel: data analysis. Olivier Tombret: data analysis. Valéry Zeitoun: data gathering, writing the manuscript

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Correspondence to Hamed Vahdati Nasab or Gilles Berillon .

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Vahdati Nasab, H., Berillon, G., Hashemi, S.M. et al. Qaleh Kurd Cave (Qazvin, Iran): Oldest Evidence of Middle Pleistocene Hominin Occupations and a Human Deciduous Tooth in the Iranian Central Plateau. J Paleo Arch 7 , 16 (2024). https://doi.org/10.1007/s41982-024-00180-4

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Collagen is the most abundant protein in the body. Its fiber-like structure is used to make connective tissue. Like the name implies, this type of tissue connects other tissues and is a major component of bone, skin, muscles, tendons, and cartilage. It helps to make tissues strong and resilient, able to withstand stretching.

In food, collagen is naturally found only in animal flesh like meat and fish that contain connective tissue. However, a variety of both animal and plant foods contain materials for collagen production in our own bodies.

Our bodies gradually make less collagen as we age, but collagen production drops most quickly due to excess sun exposure, smoking, excess alcohol, and lack of sleep and exercise . With aging, collagen in the deep skin layers changes from a tightly organized network of fibers to an unorganized maze. [1] Environmental exposures can damage collagen fibers reducing their thickness and strength, leading to wrinkles on the skin’s surface.

Collagen Supplementation

Despite its abundance in our bodies, collagen has become a top-selling supplement purported to improve hair, skin, and nails—key components of the fountain of youth. The idea of popping a pill that doesn’t have side effects and may reverse the signs of aging is attractive to many. According to Google Trends, online searches for collagen have steadily increased since 2014.

Collagen first appeared as an ingredient in skin creams and serums. However, its effectiveness as a topical application was doubted even by dermatologists, as collagen is not naturally found on the skin’s surface but in the deeper layers. Collagen fibers are too large to permeate the skin’s outer layers, and research has not supported that shorter chains of collagen, called peptides, are more successful at this feat.

Oral collagen supplements in the form of pills, powders, and certain foods are believed to be more effectively absorbed by the body and have skyrocketed in popularity among consumers. They may be sold as collagen peptides or hydrolyzed collagen, which are broken down forms of collagen that are more easily absorbed. Collagen supplements contain amino acids, the building blocks of protein , and some may also contain additional nutrients related to healthy skin and hair like vitamin C , biotin , or zinc .

What does the research say on collagen supplements?

Most research on collagen supplements is related to joint and skin health. Human studies are lacking but some randomized controlled trials have found that collagen supplements improve skin elasticity. [3,4] Other trials have found that the supplements can improve joint mobility and decrease joint pain such as with osteoarthritis or in athletes. [5] Collagen comprises about 60% of cartilage, a very firm tissue that surrounds bones and cushions them from the shock of high-impact movements; so a breakdown in collagen could lead to a loss of cartilage and joint problems.

However, potential conflicts of interest exist in this area because most if not all of the research on collagen supplements are funded or partially funded by related industries that could benefit from a positive study result, or one or more of the study authors have ties to those industries. This makes it difficult to determine how effective collagen supplements truly are and if they are worth their often hefty price.

A downside of collagen supplements is the unknown of what exactly it contains or if the supplement will do what the label promotes. There are also concerns of collagen supplements containing heavy metals. In the U.S., the Food and Drug Administration does not review supplements for safety or effectiveness before they are sold to consumers.

Another potential downside is that taking a collagen supplement can become an excuse to not practice healthy behaviors that can protect against collagen decline, such as getting enough sleep and stopping smoking.

That said, the available research has not shown negative side effects in people given collagen supplements. [3,4]

Can You Eat Collagen?

Food containing collagen

• There are foods rich in collagen, specifically tough cuts of meat full of connective tissue like pot roast, brisket, and chuck steak. However, a high intake of red meat is not recommended as part of a long-term healthy and environmentally sustainable diet . Collagen is also found in the bones and skin of fresh and saltwater fish. [2]
• Bone broth, a trending food featured prominently in soup aisles, is promoted as a health food rich in collagen. The process involves simmering animal bones in water and a small amount of vinegar (to help dissolve the bone and release collagen and minerals) anywhere from 4 to 24 hours. However, the amount of amino acids will vary among batches depending on the types of bones used, how long they are cooked, and the amount of processing (e.g., if it is a packaged/canned version).
• Gelatin is a form of collagen made by boiling animal bones, cartilage, and skin for several hours and then allowing the liquid to cool and set. The breakdown of these connective tissues produces gelatin. Collagen and its derivative, gelatin, are promoted on certain eating plans such as the paleo diet .

Foods to boost collagen production

• Several high-protein foods are believed to nurture collagen production because they contain the amino acids that make collagen—glycine, proline, and hydroxyproline. [6] These include fish, poultry, meat, eggs , dairy , legumes , and soy .
• Collagen production also requires nutrients like zinc that is found in shellfish, legumes, meats, nuts , seeds, and whole grains ; and vitamin C from citrus fruits, berries, leafy greens, bell peppers, and tomatoes.

Is bone broth healthy?

In reality, bone broth contains only small amounts of minerals naturally found in bone including calcium , magnesium , potassium , iron , phosphorus , sodium , and copper. The amount of protein , obtained from the gelatin, varies from 5-10 grams per cup.

There is some concern that bone broth contains toxic metals like lead. One small study found that bone broth made from chicken bones contained three times the lead as chicken broth made with the meat only. [7] However the amount of lead in the bone broth per serving was still less than half the amount permitted by the Environmental Protection Agency in drinking water. A different study found that bone broth, both homemade and commercially produced, contained low levels (<5% RDA) of calcium and magnesium as well as heavy metals like lead and cadmium. [9] The study noted that various factors can affect the amount of protein and minerals extracted in bone broth: the amount of acidity, cooking time, cooking temperature, and type of animal bone used. Therefore it is likely that the nutritional value of bone broths will vary widely.

Healthy Lifestyle Habits That May Help  

Along with a healthy and balanced diet , here are some habits that may help protect your body’s natural collagen:

• Wear sunscreen or limit the amount of time spent in direct sunlight (10-20 minutes in direct midday sunlight 3-4 times a week provides adequate vitamin D for most people).
• Get adequate sleep . For the average person, this means 7-9 hours a night.
• Avoid smoking or secondhand smoke.
• Control stress . Chronically high cortisol levels can decrease collagen production.
• Although the exact connection between exercise and skin quality is unclear, some studies have found that exercise slows down cell activity involved with aging skin. [10]  

Bottom Line

At this time, non-industry funded research on collagen supplements is lacking. Natural collagen production is supported through a healthy and balanced diet by eating enough protein foods , whole grains , fruits, and vegetables and reducing lifestyle risk factors.

• Rinnerhaler M, Bischof J, Streubel MK, Trost A, Richter K. Oxidative Stress in Aging Human Skin. Biomolecules . 2015 Apr 21;5(2):545-89.
• Avila Rodríguez MI, Rodriguez Barroso LG, Sánchez ML. Collagen: A review on its sources and potential cosmetic applications. Journal of Cosmetic Dermatology . 2018 Feb;17(1):20-6.
• Proksch E, Segger D, Degwert J, Schunck M, Zague V, Oesser S. Oral supplementation of specific collagen peptides has beneficial effects on human skin physiology: a double-blind, placebo-controlled study. Skin pharmacology and physiology . 2014;27(1):47-55.
• Kim DU, Chung HC, Choi J, Sakai Y, Lee BY. Oral intake of low-molecular-weight collagen peptide improves hydration, elasticity, and wrinkling in human skin: a randomized, double-blind, placebo-controlled study. Nutrients . 2018 Jul;10(7):826.
• Bello AE, Oesser S. Collagen hydrolysate for the treatment of osteoarthritis and other joint disorders: a review of the literature. Current medical research and opinion . 2006 Nov 1;22(11):2221-32.
• Lodish H, Berk A, Zipursky SL, et al. Molecular Cell Biology . New York: W. H. Freeman; 2000.
• Monro JA, Leon R, Puri BK. The risk of lead contamination in bone broth diets. Medical hypotheses . 2013 Apr 1;80(4):389-90.
• Global Market Insights. Worldwide Broth Market . Feb 26, 2018.
• Hsu DJ, Lee CW, Tsai WC, Chien YC. Essential and toxic metals in animal bone broths. Food & nutrition research . 2017 Jan 1;61(1):1347478.
• Crane JD, MacNeil LG, Lally JS, Ford RJ, Bujak AL, Brar IK, Kemp BE, Raha S, Steinberg GR, Tarnopolsky MA. Exercise‐stimulated interleukin‐15 is controlled by AMPK and regulates skin metabolism and aging. Aging cell . 2015 Aug;14(4):625-34.

Last reviewed May 2021

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• Open access
• Published: 23 May 2024

Improved pediatric ICU mortality prediction for respiratory diseases: machine learning and data subdivision insights

• Johayra Prithula 1 ,
• Muhammad E. H. Chowdhury 2 ,
• Muhammad Salman Khan 2 ,
• Khalid Al-Ansari 3 ,
• Susu M. Zughaier 4 ,
• Khandaker Reajul Islam 5 &
• Abdulrahman Alqahtani 6 , 7  

Respiratory Research volume  25 , Article number:  216 ( 2024 ) Cite this article

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The growing concern of pediatric mortality demands heightened preparedness in clinical settings, especially within intensive care units (ICUs). As respiratory-related admissions account for a substantial portion of pediatric illnesses, there is a pressing need to predict ICU mortality in these cases. This study based on data from 1188 patients, addresses this imperative using machine learning techniques and investigating different class balancing methods for pediatric ICU mortality prediction. This study employs the publicly accessible “Paediatric Intensive Care database” to train, validate, and test a machine learning model for predicting pediatric patient mortality. Features were ranked using three machine learning feature selection techniques, namely Random Forest, Extra Trees, and XGBoost, resulting in the selection of 16 critical features from a total of 105 features. Ten machine learning models and ensemble techniques are used to make accurate mortality predictions. To tackle the inherent class imbalance in the dataset, we applied a unique data partitioning technique to enhance the model's alignment with the data distribution. The CatBoost machine learning model achieved an area under the curve (AUC) of 72.22%, while the stacking ensemble model yielded an AUC of 60.59% for mortality prediction. The proposed subdivision technique, on the other hand, provides a significant improvement in performance metrics, with an AUC of 85.2% and an accuracy of 89.32%. These findings emphasize the potential of machine learning in enhancing pediatric mortality prediction and inform strategies for improved ICU readiness.

Introduction

Pediatric intensive care unit (PICU) mortality for respiratory diseases significantly impacts children’s lives and the healthcare system [ 1 ]. Such pediatric respiratory diseases as severe pneumonia, acute respiratory distress syndrome (ARDS), and respiratory failure, contribute to accounted for approximately 40% of PICU admissions, with a mortality rate ranging from 7 to 15% [ 2 , 3 ]. Pediatric mortality is steadily deteriorating on a daily basis, accompanied by an alarming decline in the infant survival rate [ 4 ]. Survivors of severe respiratory diseases in the PICU often experience long-term consequences like neurodevelopmental impairments, physical disabilities, and psychological issues. Approximately 25% of survivors of pediatric ARDS experienced new functional limitations six months after discharge [ 2 ]. PICU care for pediatric respiratory diseases incurs substantial healthcare costs [ 5 ]. The mean hospitalization cost for pediatric ARDS was approximately $67,000 [ 6 ], with an average ICU cost of $25,000 per day [ 7 , 8 , 9 ]. By investing in research, healthcare resources, and preventive measures, we can work towards reducing the impact of these diseases on children’s lives and alleviating the burden on the healthcare system [ 7 , 10 ].

Predicting pediatric mortality is of utmost importance in safeguarding young lives, enabling targeted interventions, and allocating resources to mitigate fatal outcomes [ 11 ]. Managing critically ill children with respiratory diseases demands significant medical resources, including ventilators, specialized medications, and skilled healthcare providers, which may strain the healthcare system, leading to potential shortages and increased costs [ 12 , 13 ]. The loss of a child in the PICU due to respiratory diseases has emotional and psychological impacts on families, caregivers, and healthcare providers, leading to long-term grief and mental health challenges. Early detection, effective management, and technological advancements are essential to mitigate these effects.

EHR data analysis and predictions based on machine learning models have gained popularity in recent years due to their ease of implementation and deployment [ 14 , 15 , 16 , 17 , 18 ]. The random forest model with an area under the receiver operating characteristic curve of 0.72 was used in an analysis at the Children's Hospital of Zhejiang University School of Medicine to predict postoperative mortality [ 19 ]. Another study at the University of Twente employed three classification models achieved an acceptable AUROC score of 0.71, underlining the need for additional study on methods for controlling class imbalance and model enhancement [ 20 ]. For newborns having major non-cardiac surgery, several research have developed postoperative mortality prediction models based on logistic regression [ 3 , 21 ]. Another study offers a simple but effective linear machine learning model with 11 key characteristics from a pediatric ICU dataset producing a predictive model with a ROC-AUC score of 0.7531 that beats current techniques like PRISM III (The Pediatric Risk of Mortality is a third-generation, physiology-based predictor for pediatric ICU patients [ 22 ]). The study highlights the improved efficacy and generalizability of their methods for forecasting pediatric ICU mortality.

Biochemical markers have become crucial in machine learning algorithms for accurate predictions of high-risk scenarios in pediatric patients. For instance, Early Plasma Osmolality Levels using locally weighted-regression scatterplot smoothing (LOWESS) to assess its relationship with hospital mortality, plasma osmolality at 290 mmol/L with in-, while levels below 290 mmol/L showed no significant association with mortality [ 23 ]. Serum magnesium levels were also studied, with an optimal range identified for the lowest mortality risk in critically ill children [ 24 ]. Furthermore, a study including albumin, lactate dehydrogenase, lactate, urea, arterial pH, and glucose develops a new scoring system for predicting in-hospital mortality in children outperforming the Pediatric Critical Illness Score (PCIS) showing higher AUC values in both the training and validation sets (0.81 and 0.80, respectively) [ 25 ].

Despite numerous studies on ICU mortality during COVID-19, research on pediatric populations using machine learning is limited, partly due to the scarcity of publicly available datasets. However, recently the PICU dataset [ 26 ] becomes publicly available which has made the possibility of investigating mortality prediction for different disease group. This paper focuses on enhancing mortality prediction accuracy in pediatric patients with respiratory diseases, integrating specific risk factors, biomarkers, and advanced modeling techniques.

Methodology

In this study, the publicly available PICU dataset [ 26 ] was utilized for data collection and to train, validate, and test different machine learning model. The initial dataset consisted of PICU database records and was filtered and preprocessed to remove outliers and repetitions. Three feature ranking approaches were explored to identify the optimal set of data for mortality prediction. To achieve more accurate outcomes in predicting mortality, various machine learning models, including Multilayer Perceptron (MLP) Classifier, Linear Discriminant Analysis, XGBoost Classifier, Random Forest Classifier, Logistic Regression, Support Vector Machine (SVM), Extra Trees Classifier, AdaBoost Classifier, K-Nearest Neighbors (KNN) Classifier, and Gradient Boosting Classifier, along with ensemble models, were applied to the preprocessed data. Given the highly imbalanced dynamics of the dataset (90.49% normal cases to 9.51% mortality cases), a subdivision sampling technique was implemented to obtain the most accurate predictions of mortality in pediatric patients. The prediction models for pediatric respiratory-related mortality were developed using Python software 3.9.13, and the Scikit-learn package was employed for implementing the supervised machine learning algorithms. Figure  1 displays a schematic representation of the methodology:

Step by step flowchart of the methodology

Data description

The PICU database comprises information collected during routine hospital care at The Children’s Hospital, Zhejiang University School of Medicine, from 2010 to 2019. This database follows the main schema of the MIMIC-III database but with localization-specific modifications. Standard codes, such as International Classification of Diseases (ICD-10) [ 27 ] codes for diagnosis, were used for frequently employed terms, and their English equivalents were derived. To ensure patient privacy, all identifiers required by the Health Insurance Portability and Accountability Act (HIPAA) of the United States were removed, resulting in completely de-identified patient data. The database contains a total of 13,944 ICU admissions and is structured into 16 tables [ 28 ].

Data preprocessing

The PICU database follows the framework of the MIMIC database, organized into tables for various information groupings. Before inputting this data into our machine learning model, preprocessing steps are necessary to format the database appropriately for training.

Data structuring

The database consists of 17 tables, with three dictionaries helping to interpret certain data fields, and two surgical data tables, which are not relevant to our research. Our dataset is derived from the information in the remaining 12 tables. For each patient admission case, diagnostic information is available, documented using ICD_10 codes. A mapping of ICD_10 codes to diagnose is provided in one of the dictionaries mentioned earlier. The diagnoses are categorized into admission, discharge, and clinical diagnostic categories. Additionally, the dataset includes information about the length of stay (LOS) in the ICU for each admission case, as well as physiological excretion and lab reports, which are mapped using the provided itemid (documentation of lab items mapped from the D_ITEMS table to numeric format) dictionary. The final dataset, constructed using these tables, comprises 13,941 instances and 592 columns.

Missing value removal

Out of the 592 columns used to construct the dataset, not all of them are relevant. Columns with a majority of missing data may introduce bias if imputed, so an iterative process is performed to discard columns lacking more than 70% of data. As a result, the dataset is reduced to 109 columns after discarding 483 columns.

After this reduction, each admission instance is evaluated within these 109 columns to check if the majority of column values are absent. Consequently, the initial 13,941 instances are further reduced to 12,841 instances (Fig.  2 ).

Proposed stacking ensemble technique with base models and meta-model

Filtering and outlier removal

In this study, we focused on respiratory system diseases in the diagnostic column, specifically using ICD-10 index J00-J99. Given the focus on pediatric patients, we also included congenital malformations of the respiratory system (ICD-10 index Q30–Q34). Additionally, four identifier columns were removed in this stage (Additional file 1 : Figure S1). As a result, the filtered dataset comprises a total of 1188 instances and 105 columns [ 29 ].

After filtering the data for our investigation, we conducted a detailed examination of the dataset to identify outliers. Outliers are values that do not align with medical norms as per published laboratory guidelines (Additional file 1 : Figure S2). Through a comprehensive iteration of the 105 columns in the filtered dataset, we removed values that exceeded the thresholds specified in Additional file 1 : Table S1.

Missing data imputation

Ensuring data completeness in the dataset is crucial for the success of this study. The dataset includes multiple demographic and medical biomarker data for each patient admission. However, some parameters may be missing for certain patients. Simply disregarding the available data can lead to the loss of valuable contextual information. To address this issue, data imputation is employed as an alternative to retain and fill in these missing values. Machine learning-based data imputation has been shown to be effective, and for this investigation, we utilized the MICE imputation technique [ 30 ]. Additional file 1 : Figure S3 illustrates the missing values for various characteristics in the dataset, with the spark lines on the figure’s right indicating data completeness.

Data splitting and normalization

To ensure unbiased model performance during training, the training dataset is divided into test sets using cross-validation, a well-established procedure. The entire dataset is split into 5 sets, each containing 80% training data and 20% test data [ 31 ].

For effective training of the machine learning model on the dataset, data normalization is essential to achieve generalized performance [ 32 ]. Normalization ensures that each feature contributes equally to the training process by transforming or scaling the entire dataset to a standardized range. Studies have shown improved performance when using normalized data for training instead of unprocessed data. In our study, we employed standard scalar to normalize the training data, and the scaling parameters were applied to the test set as well [ 32 ].

Data balancing

The dataset poses a fundamental challenge due to the class imbalance. While there are records for 1,075 cases (90.49%) that are alive, only 113 cases (9.51%) are deceased. This imbalance during training can introduce bias, leading the model to primarily recognize healthy cases. To mitigate this issue, a data augmentation method is proposed.

Data augmentation techniques are employed to provide synthetic data for minority classes. One such technique is Synthetic Minority Over-sampling Technique (SMOTE), a well-known method that generates synthetic data using the nearest kNN data point [ 33 ]. In our study, for both machine learning and ensemble techniques, the minority classes in the training sets are oversampled during augmentation to match the majority class.

Additionally, for the subdivision technique, each division is proportionally oversampled to achieve a balanced dataset. This approach helps address the class imbalance, enhancing the performance of the machine learning models and resulting in more accurate predictions.

Statistical analysis

The Chi-square univariate test and rank-sum test were employed to identify statistically significant characteristics between the two groups. The detailed description of this study is explained in Additional file 1 : S1. This analysis calculates the difference between the observed frequency (O) and the expected frequency (E) for each cell. It then squares the difference, divides it by the expected frequency, and sums the results for all cells in the contingency table [ 34 , 35 ].

Feature ranking

In the preprocessed dataset containing 105 features and a column with target variables, using all features may lead to overfitting and impractical deployment for real-time prediction. To select the most relevant features, three machine learning feature selection models are employed: XGboost, RandomForest and Extratrees. Descriptions of these feature ranking techniques are given in Additional file 1 : S2.

Using these feature selection models, we can identify the most relevant features to enhance prediction accuracy while avoiding overfitting and ensuring practical deployment in real-time scenarios.

Machine learning model development

This study explores several machine learning models from the Sci-kit learn library. We trained our data on MLP Classifier, Linear Discriminant Analysis, XGBoost Classifier, Random Forest Classifier, Logistic Regression, SVM, Extra Trees Classifier, Ada Boost Classifier, KNN Classifier, and Gradient Boosting Classifier [ 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 ]. Notably, Extra Trees, Random Forest and Catboost classifier demonstrated the most promising performance. In the subsequent section, a comprehensive overview of these top-performing models is provided:

Extra trees classifier

Extremely Randomized Trees, or ExtraTrees (ET) Classifier, is a tree-based ensemble technique used in supervised learning. This model introduces extreme randomness in attribute values and tree node cutoff points. It is a subset of the RandomForest classifier, offering computational efficiency through more extensive randomization. The classification score measurement for ExtraTrees is a specific normalization of information gain. For a sample S and a division s, the measure is given by:

where \({H}_{s}(S)\) is the (log) entropy of the classification in S, \({H}_{s}(S)\) is the split entropy (also called split information by Quinlan (1986)), and \({I}_{c}^{s}\left(S\right)\) is the mutual information of the split outcome and the classification [ 42 , 46 , 47 ].

Random forest classifier

The Random Forest (RF) Classifier is a classification-focused machine learning algorithm that uses an ensemble approach by combining multiple decision trees. The term “random forest” comes from the fact that the algorithm creates a forest of decision trees with arbitrary constructions. Important division points in the data, like Gini impurity or information gain, are used to build decision trees based on different criteria. However, in Random Forest, the selection of split points is limited to a random subset of features at each node, rather than considering all features [ 39 , 48 , 49 ]. Additional file 1 : Figure S4 depicts the framework for the RandomForest Classifier.

Catboost classifier

CatBoost (CB) Classifier is a gradient boosting algorithm tailored for efficient handling of categorical features. By constructing decision trees and combining their predictions, it achieves accurate classifications. This specialized algorithm efficiently manages categorical features, feature scaling, and missing values, optimizing training performance. Compared to conventional gradient boosting algorithms, CatBoost offers a more streamlined and automated approach [ 50 , 51 ].

Stacking based machine learning model

Ensemble models are employed when individual models fall short of achieving desired outcomes [ 52 , 53 ]. This method has found extensive application, including in medical applications, where it proves effective in improving the accuracy of predictions by leveraging insights from various models [ 16 , 54 , 55 ]. Stacking ensemble technique is used in this study, combining the predictions of our top three models. Stacking ensemble, also known as stacked generalization, involves training a meta-model to optimally combine base models' predictions, resulting in improved overall performance. By utilizing input x and the predictions of the base-level classifier set M, a probability distribution is created, leading to a final prediction:

where ( \({{\text{c}}}_{1}\) , \({{\text{c}}}_{2}\) … \({{\text{c}}}_{{\text{m}}}\) ) represents the set of potential class values and \({{\text{P}}}^{{\text{M}}}\left({{\text{c}}}_{{\text{i}}}|{\text{x}}\right)\) represents the probability that example x belongs to class \({{\text{c}}}_{{\text{i}}}\) , as calculated (and predicted) by classifier M [ 52 , 53 ]. This investigation employs the classifiers Extra-trees, RandomForest, and CatBoost. The Gradient boosting classifier was used for the meta-model. Our proposed architecture for the stacking ensemble method is depicted in Fig.  2 below:

Data subdivision: an approach for highly imbalances datasets

The main challenge in our study is the significant class disparity, with a distribution of 90.49% to 9.51%, which can lead to biased predictions and an inability to accurately predict the minority class. To address this issue, we explore different techniques to mitigate data imbalance, namely undersampling and oversampling. Undersampling involves reducing the number of samples from the majority class to equalize class distribution. However, this approach results in the loss of valuable information, as a considerable percentage of data is discarded. On the other hand, oversampling aims to increase the number of samples in the minority class by duplicating data points, but applying this method to highly imbalanced datasets can lead to overfitting. The model becomes too reliant on the specific minority data points, leading to inaccuracies in predicting new data.

To overcome these challenges, we propose a subset method for handling imbalanced data in our study. We divide the majority class into three subsets and then create three Subdivisions by combining each subset with an oversampled version of the entire minority class. This division of the dataset into smaller Subdivisions helps reduce class disparity compared to the complete dataset. As a result, when oversampling is applied, it encounters a much lower discrepancy and generates fewer duplications of the minority data points, reducing the risk of overfitting. During the training process, we apply fivefold Cross-Validation for each Subdivision and use SMOTE to achieve class balance in the training set of each fold. The results of each Subdivision are later averaged to obtain the final prediction. This approach ensures that each Subdivision is given equal importance, and the ensemble of results helps improve overall performance. Figure  3 illustrates the data subdivision technique used in our study, depicting how the dataset is divided into Subdivisions, oversampled, and finally combined to achieve more balanced training data.

Data subdivision technique

By adopting the data subdivision technique, we aim to enhance the accuracy and reliability of our machine learning models in predicting the minority class while avoiding the pitfalls of traditional undersampling and oversampling methods. This innovative approach contributes to more robust and effective predictions in our study, paving the way for improved results in handling imbalanced data sets in various domains.

To balance the dataset, we divided the majority class into three subsets (359, 359, and 357 cases) and merged them with the minority class (113 instances). SMOTE was then used to achieve class balance.

Performance metrics

The receiver operating characteristic (ROC) curves and area under the curve (AUC), along with Precision, Sensitivity, Specificity, Accuracy, and F1-Score, were used to evaluate the performance of the classifiers. In addition, we utilized five-fold cross-validation, which results in a division of 80% and 20% for the train and test sets, respectively, and according to the fold number, this procedure is repeated five times to validate the entire dataset.

We utilized per-class weighted metrics and overall precision because the number of instances varied between classes. In addition, the AUC value was utilized as an evaluation metric. Five evaluation metrics (weighted sensitivity or recall, specificity, precision, overall accuracy, and F1 score) are represented mathematically in Eqs.  3 through 7 .

here true positive, true negative, false positive, and false negative are represented as TP, TN, FP, and FN, respectively.

Experimental setup

This study was carried out with the sklearn package and Python 3.9.13. All the models were trained with the specifications: Nvidia GForce 1050ti GPU, AMD Ryzen 7 5800X 8-Core Processor and 32 GB High RAM.

The statistical analysis was conducted using the scipy library and the chi-square test on our dataset. Demographic variables were excluded from the analysis, leaving continuous numeric columns. The chi-square rank-sum test was used to assess the statistical significance of individual characteristics for each group, with a significance threshold of P < 0.05. The dataset consisted of 1075 (90.49%) living cases and 113 (9.51%) deceased cases. The mean (SD) value of lactate for deceased cases was 9.99 (7.42), while for living cases, it was 3.63 (2.92). ALB/GLB and Chloride_Whole_Blood had P-values greater than 0.8, indicating no significant difference between the groups. The P-values for Creatine_Kinase (CK), Mean_Platelet_Volume (MPV), thrombin_time, Hematocrit, WBC_Urine, WBC/pus_cell, and Monocyte_Count ranged from 0.79 to 0.50. Additional file 1 : Table S2 presents the class-wise mean, standard deviation, and P-values for all biochemical markers and continuous variables.

In this study, three machine learning feature selection models were employed: XGBoost, RandomForest, and Extra trees. In the initial analysis, RandomForest yielded the most favorable rankings, resulting in higher accuracy scores for predictions compared to the other two methods. Out of the 106 features, the top 16 features were identified as the most effective for achieving optimal results with a minimal number of features. Figure  4 illustrates the F1-Scores for class 1 corresponding to the top features in our three best models.

F1-Scores for Class 1 across the top features

In Fig.  5 , the top 20 characteristics assessed by RandomForest are presented, and out of these, 16 were utilized. Among them, lactate was identified as the most significant characteristic.

Features ranked according to Random Forest feature selection algorithm

Machine learning model performances

The top 16 features, as ranked by Random Forest's feature importance attribute, along with the ‘HOSPITAL_EXPIRE_FLAG’ as the target variable, were used to train the algorithms. The models were then tested using fivefold cross-validation on the entire dataset. The performance of the top three machine learning models was investigated and evaluated. In the following section, we present and discuss the results of each experiment.

The ET classifier achieved an AUC score of 72.22% and an accuracy of 89.14%. However, its class-wise precision for the deceased class (class 1) was only 43.94%, indicating poor performance in accurately detecting the deceased cases. The RF classifier obtained an AUC score of 70.91% and an accuracy of 88.22%. However, when analyzing individual classes, the precision for class 1 was found to be 40.28%. The CB classifier demonstrates the highest AUC (77.11%) and accuracy (87.96%) among the three classifiers. However, it exhibits lower precision (41%) in predicting the deceased class compared to other classifiers. The stacking technique was employed to create an ensemble model by combining the top three performing models. The layered models were trained using gradient boosting classifier. As a result, the AUC score decreased to 60.59%, while the accuracy increased to 88.89%. Table 1 provides a summary of the results for the ET, RF, CB and stacking ML classifiers.

Figure  6 shows the confusion matrix for Extra Tree, Random Forest, CatBoost and stacking ML model. It is apparent that among these models CatBoost is performing the best in terms of sensitivity and AUC. However, none of the models are showing acceptable performance in this highly imbalance dataset (d). The ROC curves for ET, RF, CB and stacking ML model can be seen in Fig.  7 .

Confusion matrix for Extra Tree ( a ), Random Forest ( b ), CatBoost ( c ) and stacking ensemble method ( d )

ROC curves for Extra Tree ( a ), Random Forest ( b ), CatBoost ( c ) and stacking ensemble method ( d )

Data subset performances

Utilizing the top 16 features, we employ the CB classifier for the subdivision method. Dividing the dataset into three subdivisions, we independently train each subset on the CB model and then aggregate the results by averaging them. The subdivision method exhibits a noteworthy average subset accuracy of 89.32% with an AUC of 85.20%. The precision and sensitivity for this model are 77.98% and 77.29%, respectively, while the specificity and F1-score stand at 93.11% and 89.30%. For a visual representation of the model’s performance, refer to Fig.  8 , which illustrates the ROC curve for the subdivision method. The summary of the average result of the subdivision method and results for each subdivision is stated in Table  2 and 3 .

Confusion matrix for the subsets for the best performing model—CB Classifier and average ROC curve for the subdivision technique

The confusion matrix for each subset and average ROC curve are depicted in Fig.  8 .

The findings of this study showcase the significant potential of biomarkers in predicting mortality, offering valuable insights that can aid clinicians in making well-informed decisions. In our exploration of feature selection models for machine learning, namely XGBoost, RandomForest, and Extra tree, we discovered that the top 16 features selected by RandomForest yielded the most optimal results with minimal feature utilization during the initial investigations. This indicated that RandomForest outperformed its competitors in terms of predictive performance.

However, upon conducting further analysis, we unveiled certain limitations of the classifiers, particularly their inability to accurately predict the deceased class. Despite the promising results and efficiency of RandomForest in feature selection, it became evident that more advanced techniques were necessary to tackle the challenge of effectively predicting mortality in the dataset. This highlighted the importance of continually exploring and refining machine learning methodologies to enhance their predictive capabilities and address specific complexities in clinical scenarios. As such, our study not only underscores the significance of biomarkers in mortality prediction but also emphasizes the ongoing need for sophisticated algorithms to achieve more accurate and comprehensive predictions in critical healthcare settings.

We focused on the subdivision technique using the top 16 features for the CB classifier. Dividing the dataset into three distinct subsets, we proceeded to train each of these subsets independently on the CB model. Subsequently, the results were skillfully combined by averaging them, yielding a highly commendable average subset accuracy of 89.32%. Moreover, the AUC for this method achieved an impressive 85.2%, indicative of its robustness in discrimination capability. As a result of this approach, not only did we achieve superior accuracy, but we also observed significant improvements in precision, sensitivity, specificity, and F1-score, all of which are crucial performance metrics in medical predictive modeling. These outcomes underscore the effectiveness of the subdivision technique and its potential to further enhance the reliability and precision of our predictive model.

However, while the CB classifier excelled in predicting the living cases, it exhibited limitations when it came to accurately predicting the deceased class. The model struggled to achieve satisfactory performance in detecting the minority class of deceased cases, resulting in lower sensitivity and F1-score values. This indicates that additional research and further refinement are essential to enhance the model's ability to accurately predict the deceased class. To address these identified limitations, future investigations could focus on improving the handling of imbalanced data and exploring more advanced ensemble techniques or hybrid models that may provide a better balance between the two classes. Moreover, fine-tuning the feature selection process and incorporating domain-specific knowledge may also contribute to enhancing the model's predictive capabilities for the deceased class. A quantitative comparison among relevant studies is provided in Table  4 .

The data size in our study, encompassing 13,944 pediatric ICU cases, is comparable to that in Hong et al.’s study and larger than the datasets used in other referenced studies. This extensive data size provides a robust basis for our analysis and enhances the generalizability of our results. Our approach, focusing on feature engineering and data subdivision, yielded an accuracy of 0.8932 and an AUC of 0.8520. These results are notably higher than those achieved in the studies by Hu et al., Wang et al., and Zhang et al., indicating a strong predictive capability of our model. It is noteworthy that our study’s AUC is comparable to that achieved by Li et al., who employed advanced fusion models.

The variance in approaches and outcomes across these studies underscores the diverse methodologies in mortality prediction research. Our study contributes to this growing body of work by demonstrating the efficacy of feature engineering combined with data subdivision techniques in a pediatric ICU setting. This approach shows promise in enhancing predictive accuracy and could be a valuable addition to the clinician’s toolkit for mortality prediction, emphasizing the need for personalized and data-driven patient care. This comparative analysis not only positions our study within the existing research landscape but also highlights its potential clinical utility and relevance. By benchmarking our findings against these studies, we gain valuable insights into the evolving nature of machine learning applications in healthcare and identify avenues for future research and development in predictive modeling for pediatric respiratory diseases. The findings of this study need to be approached with caution due to the limitations posed by the relatively small dataset size and the class imbalance between deceased and living cases. The restricted sample size may impact the generalizability and robustness of the results. Furthermore, the class imbalance can introduce biases and hinder the accurate prediction of the minority class. To enhance the credibility and efficacy of mortality prediction models for pediatric patients with respiratory diseases, future research endeavors should focus on gathering larger and more balanced datasets. By increasing the sample size, the models can be trained on a more diverse and representative set of instances, leading to improved performance and better generalization to real-world scenarios. In addition to dataset size and class balance, researchers should also explore the incorporation of additional relevant features and biomarkers to refine the predictive models further. Integrating comprehensive and diverse patient data can enable the development of more comprehensive and accurate mortality prediction systems. Moreover, it is essential to conduct external validation of the developed models on independent datasets to verify their reliability and effectiveness in different healthcare settings. This validation process will provide crucial insights into the model’s robustness and its potential to be applied in diverse clinical environments.

Monitoring ICU patients’ parameters (lactate, pCO2, LDH, anion gap, electrolytes, INR, potassium, creatinine, bicarbonate and WBC) provide valuable insights into their pathophysiology i.e. medical progress and severity of critical illness, which help in guiding treatment or decision-making. The following explains the significance of the top parameters: elevated lactate levels indicate tissue hypoxia and anaerobic metabolism, often seen in shock or hypo perfusion states of ICU patients. Monitoring lactate helps assess tissue perfusion and response to treatment. Carbon dioxide (pCO2) is a byproduct of metabolism and is eliminated through respiration. Changes in pCO2 can indicate respiratory status and acid–base balance, especially in patients with respiratory failure or ventilation issues. Lactate Dehydrogenase (LDH) is an enzyme found in various tissues, including the heart, liver, and muscles. Elevated LDH levels can indicate tissue damage or breakdown, as seen in conditions like myocardial infarction, liver disease, or muscle injury. The elevated levels of LDH reflect the severity of critical illness. Whereas the anion gap is a calculated parameter that helps assess metabolic acidosis. An increased anion gap may indicate the presence of unmeasured anions, such as lactate, ketones, or toxins, which can be seen in conditions like diabetic ketoacidosis or lactic acidosis conditions that require extensive monitoring in ICU. Therefore, monitoring electrolytes like sodium, potassium, and chloride helps assess fluid and electrolyte balance, which is crucial in critically ill patients to prevent complications like arrhythmias or neurologic abnormalities. Potassium in particular is essential for proper cardiac and neuromuscular function. Abnormal potassium levels can lead to life-threatening arrhythmias and are often seen in conditions like renal failure or metabolic disorders. Bicarbonate is a buffer that helps maintain acid–base balance in the body. Changes in bicarbonate levels can indicate metabolic acidosis or alkalosis, which can occur in various critical illnesses. Creatinine is a waste product of muscle metabolism and is excreted by the kidneys. Elevated creatinine levels indicate impaired renal function, which is common in critically ill patients and can impact drug dosing and fluid management. Monitoring WBC (White Blood Cell Count helps assess the inflammatory response and immune function in critically ill patients. Elevated WBC counts may indicate infection or inflammatory processes. Similarly, monitoring PCT (procalcitonin) as biomarker of bacterial infections. Additionally, INR (International Normalized Ratio) is a measure of blood coagulation and is used to monitor patients on anticoagulant therapy. Changes in INR can indicate alterations in the coagulation cascade and may require adjustments in medication [ 58 , 59 , 60 , 61 ].

In summary, addressing the limitations of dataset size and class imbalance and incorporating advanced feature selection techniques and external validation can advance the accuracy and dependability of mortality prediction models for pediatric patients with respiratory diseases. These efforts will ultimately contribute to more effective and personalized patient care, leading to improved clinical outcomes for this vulnerable patient population.

In conclusion, this study sheds light on the promising potential of biomarkers in predicting mortality among pediatric patients with respiratory diseases, empowering clinicians to make well-informed admission decisions. Through meticulous evaluation of diverse classifiers, the CatBoost (CB) classifier emerged as the standout performer, exhibiting the highest AUC score and accuracy. However, the challenge lies in improving precision for the deceased class. By employing the stacking ensemble method, we were able to enhance overall accuracy, albeit at the expense of a slightly lower AUC score. Subsequently, the subdivision technique applied to the CB classifier using the top 16 features led to remarkable improvements in precision (89.32%), AUC (85.20%), and other essential predictive metrics. Overall, the CB classifier with the subdivision algorithm proved to be the most effective approach for mortality prediction. Looking ahead, our future objectives for this mortality prediction model in pediatrics encompass its seamless integration into clinical settings, especially in resource-constrained environments, and customization to suit the needs of specific populations. Additionally, we aim to incorporate real-time data streams to ensure up-to-date and accurate predictions. Collaborative efforts to enhance the dataset’s size and diversity are paramount to ensure the model’s robustness and generalizability. By diligently pursuing these avenues, we envision a significant impact on pediatric healthcare, as our model’s enhanced accuracy will bolster preparedness and improve patient outcomes, ultimately saving lives and benefiting young patients and their families.

Availability of data and materials

The preprocessed version of the dataset used in this study is available upon reasonable request to the corresponding author.

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This work was made possible by High Impact grant# QUHI-CENG-23/24-216 from Qatar University and is also supported via funding from Prince Sattam Bin Abdulaziz University project number (PSAU/2023/R/1445). The statements made herein are solely the responsibility of the authors.

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Johayra Prithula

Department of Electrical Engineering, Qatar University, 2713, Doha, Qatar

Muhammad E. H. Chowdhury & Muhammad Salman Khan

Emergency Medicine Department, Sidra Medicine, Doha, Qatar

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Susu M. Zughaier

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Conceptualization: JP, MEHC; Data curation: JP, KRI; Formal analysis: JP; Funding acquisition: MEHC, MSK, KA, SMZ, AA; Investigation: JP, MEHC; Project administration: MEHC, MSK, AA; Software: JP, KRI; Supervision: MEHC, MSK, AA; Validation: MEHC, KA, SMZ; Visualization: JP; writing—original draft: JP, MEHC, AA; Writing—review & editing: JP, MEHC, MSK, KA, SMZ, KRI, AA.

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Prithula, J., Chowdhury, M.E.H., Khan, M.S. et al. Improved pediatric ICU mortality prediction for respiratory diseases: machine learning and data subdivision insights. Respir Res 25 , 216 (2024). https://doi.org/10.1186/s12931-024-02753-x

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DOI : https://doi.org/10.1186/s12931-024-02753-x

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The Graceful Crane: Symbolism and Significance in Japanese Culture

Myths about the majestic crane can be found in countries all over the world. However, the crane in Japanese mythology is by far the most fascinating of them all. In this post, we’ll guide you through the myths, facts, symbolism, and folklore associated with one of Japan’s most revered creatures. 

Introduction to the Crane in Japan: Grace and Elegance Personified

Based on science, the crane is a type of bird. It’s large and has a distinct, long neck and legs. There are about 15 different species of crane, which possess a variety of colors, including white, gray, brown, and gold brown. They typically have black or red facial patches. When they fly, their long necks and legs are stretched out.

Cranes are naturally occurring on almost every continent. In Asia, several species of birds can be found in Japan, where they are revered for their beauty, grace, and symbolic significance. The crane in Japan is a national treasure, and the bird plays a prominent role in the country’s mythology, folklore, art, and literature. As a mystical and holy bird, it is at the heart of the Japanese origami tradition of paper folding.

Many believe that the crane can live for a thousand years. Hence, it’s a nation-wide symbol of good luck, happiness, hope, peace, and longevity. Different regions of Japan also have their own cultural practices and beliefs that revolve around this majestic bird.

Crane in Japanese Mythology: Tales of Wisdom and Longevity

The tsuru , which is a Japanese term for crane, takes on an important role in Japanese mythology. It’s one of the mythical holy creatures and is often portrayed similarly to how the tortoise and the dragon are in Japanese culture. As a messenger of the gods, the crane is believed to be a bird of happiness, and popular myths suggest that it possesses several magical powers. Some of these mythical abilities include longevity lasting up to 1,000 years and the ability to grant wishes.

There is an ancient, but highly significant, legend that a crane will grant one wish to anyone who folds a thousand paper cranes (origami). This practice is a symbol of hope that transcends Japanese mythology and extends into real life due to historic events, including the tragic story of Sadako Sasaki. We’ll reveal more on that later in this post.

Symbolism of the Crane in Japan: Peace, Prosperity, and Good Fortune

In Japan, the crane represents a lot of traits, values, and virtues. Its appearance, behavior, and the myths surrounding its existence all contribute to this symbolism. Let’s explore some of the symbolic meanings associated with the crane in Japan:

Good luck: Seeing a crane is considered good luck because of its role as a messenger of the gods. Folding a paper Japanese crane (origami) or using crane-inspired art at events like weddings and New Year celebrations is also said to bring good luck. 

Longevity: Cranes can live for multiple decades, which is long for a bird. Hence the myth that it lives for 1,000 years. That is why the crane is seen as a symbol of longevity.

Fidelity: Cranes stay with their mates for life. Hence, they represent fidelity in marriages and relationships.

Happiness: In Shinto religion, the crane has close ties to the god of happiness. 

Strength: The crane has a tall frame and strong flight pattern, which makes it a symbol of strength and power.

Auspiciousness: Cranes often symbolize the promise of a successful outcome, especially during New Year celebrations and marriage ceremonies.

Hope: The image of the crane is considered a sign of hope during challenging times.

Peace: Cranes and their origami portrayals represent peace in Japan and other countries of the world.

Crane in Japanese Art: A Symbol of Beauty and Inspiration

For centuries, there have been countless depictions of cranes in Japanese art, ranging from ancient scrolls and paintings to contemporary designs. These art pieces reflect their enduring allure and embody their cultural symbolism. In textile art and designs, the crane makes appearances in uchikake kimono (traditional Japanese bridal gowns), obi, and other traditional wear. These fashion items are typically decorated with embroidered images of white cranes to symbolize fidelity, longevity, and good luck during traditional ceremonies.

The natural beauty of cranes is also celebrated with the art of pottery, where people make ceramic and porcelain wares with images of the stunning birds. You’ll find hand-drawn designs on cups, bulbous vases, casks, bowls, and barrels. During the Meiji period (1868–1912), high-quality metal work inspired by cranes was quite popular. These pieces ranged from bronze sculptures to mixed-metal kettles and vases.

The crane is also depicted in wall and floor screens, woodblock prints, paintings, and scrolls that decorate temples, shrines, palaces, and the homes of the Japanese elite. Sosaku kokeshi, which are modern versions of the ancient armless and pin-shaped dolls, are often designed with crane images and given to married couples as gifts. Photographers are not left out, as many of them take pictures of the famous red-crowned crane and sell them online or in art galleries.

Cranes in Japanese Folklore: Legends and Folk Beliefs

The folk tales and beliefs surrounding cranes in Japan are some of the most meaningful in the country. They often tell tales of luck, protection, and the afterlife, which are valuable concepts in Asian culture.

One of the most famous folklores in Japan is called Tsuru no Ongaeshi (The Crane's Return of a Favor). It tells the story of a man’s encounter with the creature. The sight of a crane falling from the sky startled a young man who was working on his farm in Hokkaido, Japan. A bird hunter had injured it by piercing its wings with an arrow. The young man nursed the crane back to health and it flew away.

When he returned home, he was shocked to find a beautiful woman waiting for him. She called herself his wife. At first, the man protested, citing his lack of wealth as the reason he could not keep a wife. However, she offered him a sack of rice, which she promised would provide them with an abundance of food. True to her words, the sack always stayed full of rice. One day, she made the man build her a weaving room, which he was never to peek into. He agreed and she went in. Seven days later, she came out with a beautiful piece of cloth, asking him to sell it at the market. He sold the cloth for a lot of money and returned as a wealthy man.

She went into the weaving room again, but this time, the curious young man peeked. He was shocked to find the crane he saved weaving the beautiful linen with its own feathers. Because he had seen her true form, the crane could no longer stay, and she flew away, leaving him with another beautiful cloth. She never returned.

There are many variants of this story, including Tsuru Nyōbō (The Crane Wife), in which the man marries a woman who is secretly a crane. She weaves him expensive clothing, but each one takes a toll on her health. He eventually finds out and convinces her to stop.

Origami Cranes: Folding Peace and Hope in Japanese Tradition

In general, origami is the Japanese art of paper folding. However, the making of a paper crane or orizuru , is its most meaningful form. Origami cranes are folded as symbols of peace, healing, and remembrance. There is a cultural belief that one who folds a thousand cranes will experience good luck for all eternity and will also have their wishes granted by the gods. That is why origami cranes are offered to sick or injured people as a way to wish them good luck and a speedy recovery.

In 1945, something happened that would solidify the origami crane as a symbol of peace and hope. This was the year of the nuclear bombing of Hiroshima and Nagasaki during World War II. A two-year-old girl named Sadako Sasaki, who lived in Hiroshima when it happened, was affected by the radiation. She was diagnosed with leukaemia ten years later and admitted to the hospital. She spent her time in the hospital folding origami cranes in the hopes that she would get well. Sadly, Sadako died after eight months in the hospital.

In honor of Sadako Sasaki and other innocent children affected by the war, the Children’s Peace Monument was built in Hiroshima Peace Memorial Park. It is a statue of Sadako holding a crane, and people fold cranes and place them at the site. Each year, students and visitors offer about 10 million paper cranes to the monument. The story of Sadako has made the orizuru a global symbol of peace, healing, and remembrance.

Crane Conservation Efforts in Japan: Protecting a National Treasure

Since the turn of the 20th century, there have been multiple conservation efforts by the Japanese government, non-profit groups, and local residents to preserve these majestic birds for future generations. All these became necessary when the most revered crane species, the red-crowned crane, neared global extinction. At the time, there were 4,000 of them left worldwide and only 36 in Japan. Over the decades, the creation of sanctuaries and other conservation efforts in Kushiro, where the remaining birds were found, has helped bolster the number of red-crowned cranes in Japan to over 1,900.

Crane Sanctuaries in Japan: Preserving Natural Habitats

If you want to see canes in their natural habitats, you should visit one of their sanctuaries and wildlife reserves in Japan. The following is a list of places where visitors can watch the Japanese cranes, take photos, and learn about conservation efforts.

Tsurui Ito Tancho Crane Sanctuary: It was created by Japan’s Wild Bird Society and the late Yoshitaka Ito and his wife. The sanctuary is located in the Akan District of Hokkaido.

Tsurumidai Feeding Point: This is a popular bird-feeding spot in Kushiro City, Hokkaido. 

Akan International Crane Center: It’s a zoology museum located in Kushiro that specializes in both the conservation and research of cranes.

Japanese Crane Reserve: This is a sightseeing natural park in Kushiro that doubles as a reserve for the red-crowned crane.

Crane Symbolism Around the World: Comparisons and Cultural Significance

Japan is not the only country with a nation-wide interest in cranes. The bird has symbolic significance in many other countries, particularly those within Asia. Crane symbolism in China is identical to that in Japan. It represents good fortune, longevity, and immortality. It also symbolizes grace and wisdom in Chinese literature. Native Americans also see cranes as symbols of longevity and good fortune.

In Greek mythology, cranes are considered messengers of the gods, especially Apollo, the sun god. They symbolize intelligence and the afterlife, and their dance is seen as a celebration of life. In African cultures, the crane is often associated with nobility, patience, focus, and wisdom.

Conclusion: Embracing the Legacy of the Crane in Japan

By maintaining its role as a cherished cultural icon over many decades, the crane continues to inspire and captivate people from all over the world. The next time you see a crane, we hope that you appreciate its significance in Japanese culture as an enduring symbol of peace, prosperity, and beauty.

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