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Neal Haddaway

October 19th, 2020, 8 common problems with literature reviews and how to fix them.

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Literature reviews are an integral part of the process and communication of scientific research. Whilst systematic reviews have become regarded as the highest standard of evidence synthesis, many literature reviews fall short of these standards and may end up presenting biased or incorrect conclusions. In this post, Neal Haddaway highlights 8 common problems with literature review methods, provides examples for each and provides practical solutions for ways to mitigate them.

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Researchers regularly review the literature – it’s an integral part of day-to-day research: finding relevant research, reading and digesting the main findings, summarising across papers, and making conclusions about the evidence base as a whole. However, there is a fundamental difference between brief, narrative approaches to summarising a selection of studies and attempting to reliably and comprehensively summarise an evidence base to support decision-making in policy and practice.

So-called ‘evidence-informed decision-making’ (EIDM) relies on rigorous systematic approaches to synthesising the evidence. Systematic review has become the highest standard of evidence synthesis and is well established in the pipeline from research to practice in the field of health . Systematic reviews must include a suite of specifically designed methods for the conduct and reporting of all synthesis activities (planning, searching, screening, appraising, extracting data, qualitative/quantitative/mixed methods synthesis, writing; e.g. see the Cochrane Handbook ). The method has been widely adapted into other fields, including environment (the Collaboration for Environmental Evidence ) and social policy (the Campbell Collaboration ).

limitations in literature review

Despite the growing interest in systematic reviews, traditional approaches to reviewing the literature continue to persist in contemporary publications across disciplines. These reviews, some of which are incorrectly referred to as ‘systematic’ reviews, may be susceptible to bias and as a result, may end up providing incorrect conclusions. This is of particular concern when reviews address key policy- and practice- relevant questions, such as the ongoing COVID-19 pandemic or climate change.

These limitations with traditional literature review approaches could be improved relatively easily with a few key procedures; some of them not prohibitively costly in terms of skill, time or resources.

In our recent paper in Nature Ecology and Evolution , we highlight 8 common problems with traditional literature review methods, provide examples for each from the field of environmental management and ecology, and provide practical solutions for ways to mitigate them.

There is a lack of awareness and appreciation of the methods needed to ensure systematic reviews are as free from bias and as reliable as possible: demonstrated by recent, flawed, high-profile reviews. We call on review authors to conduct more rigorous reviews, on editors and peer-reviewers to gate-keep more strictly, and the community of methodologists to better support the broader research community. Only by working together can we build and maintain a strong system of rigorous, evidence-informed decision-making in conservation and environmental management.

Note: This article gives the views of the authors, and not the position of the LSE Impact Blog, nor of the London School of Economics. Please review our  comments policy  if you have any concerns on posting a comment below

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About the author

limitations in literature review

Neal Haddaway is a Senior Research Fellow at the Stockholm Environment Institute, a Humboldt Research Fellow at the Mercator Research Institute on Global Commons and Climate Change, and a Research Associate at the Africa Centre for Evidence. He researches evidence synthesis methodology and conducts systematic reviews and maps in the field of sustainability and environmental science. His main research interests focus on improving the transparency, efficiency and reliability of evidence synthesis as a methodology and supporting evidence synthesis in resource constrained contexts. He co-founded and coordinates the Evidence Synthesis Hackathon (www.eshackathon.org) and is the leader of the Collaboration for Environmental Evidence centre at SEI. @nealhaddaway

Why is mission creep a problem and not a legitimate response to an unexpected finding in the literature? Surely the crucial points are that the review’s scope is stated clearly and implemented rigorously, not when the scope was finalised.

  • Pingback: Quick, but not dirty – Can rapid evidence reviews reliably inform policy? | Impact of Social Sciences

#9. Most of them are terribly boring. Which is why I teach students how to make them engaging…and useful.

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Eight problems with literature reviews and how to fix them

Affiliations.

  • 1 Mercator Research Institute on Climate Change and Global Commons, Berlin, Germany. [email protected].
  • 2 Stockholm Environment Institute, Stockholm, Sweden. [email protected].
  • 3 Africa Centre for Evidence, University of Johannesburg, Johannesburg, South Africa. [email protected].
  • 4 College of Medicine and Health, Exeter University, Exeter, UK.
  • 5 Department of Zoology, University of Cambridge, Cambridge, UK.
  • 6 School of Biological Sciences, University of East Anglia, Norwich, UK.
  • 7 Department of Biological Sciences, Royal Holloway University of London, Egham, UK.
  • 8 Stockholm Environment Institute, Stockholm, Sweden.
  • 9 Department of Zoology, University of Oxford, Oxford, UK.
  • 10 Collaboration for Environmental Evidence, UK Centre, School of Natural Sciences, Bangor University, Bangor, UK.
  • 11 Liljus ltd, London, UK.
  • 12 Department of Forest Sciences, University of Helsinki, Helsinki, Finland.
  • 13 Evidence Synthesis Lab, School of Natural and Environmental Sciences, University of Newcastle, Newcastle-upon-Tyne, UK.
  • PMID: 33046871
  • DOI: 10.1038/s41559-020-01295-x

Traditional approaches to reviewing literature may be susceptible to bias and result in incorrect decisions. This is of particular concern when reviews address policy- and practice-relevant questions. Systematic reviews have been introduced as a more rigorous approach to synthesizing evidence across studies; they rely on a suite of evidence-based methods aimed at maximizing rigour and minimizing susceptibility to bias. Despite the increasing popularity of systematic reviews in the environmental field, evidence synthesis methods continue to be poorly applied in practice, resulting in the publication of syntheses that are highly susceptible to bias. Recognizing the constraints that researchers can sometimes feel when attempting to plan, conduct and publish rigorous and comprehensive evidence syntheses, we aim here to identify major pitfalls in the conduct and reporting of systematic reviews, making use of recent examples from across the field. Adopting a 'critical friend' role in supporting would-be systematic reviews and avoiding individual responses to police use of the 'systematic review' label, we go on to identify methodological solutions to mitigate these pitfalls. We then highlight existing support available to avoid these issues and call on the entire community, including systematic review specialists, to work towards better evidence syntheses for better evidence and better decisions.

  • Environment
  • Research Design
  • Systematic Reviews as Topic*

Eight common problems with science literature reviews and how to fix them

limitations in literature review

Research Fellow, Africa Centre for Evidence, University of Johannesburg

Disclosure statement

Neal Robert Haddaway works for the Stockholm Environment Institute and the Mercator Research Institute on Global Commons and Climate Change. He receives funding from the Alexander von Humboldt Foundation, Mistra, Formas, and Vinnova. He is also an honorary Research Associate at the Africa Centre for Evidence at the University of Johannesburg.

University of Johannesburg provides support as an endorsing partner of The Conversation AFRICA.

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Researchers regularly review the literature that’s generated by others in their field. This is an integral part of day-to-day research: finding relevant research, reading and digesting the main findings, summarising across papers, and making conclusions about the evidence base as a whole.

However, there is a fundamental difference between brief, narrative approaches to summarising a selection of studies and attempting to reliably, comprehensively summarise an evidence base to support decision-making in policy and practice.

So-called “evidence-informed decision-making” relies on rigorous systematic approaches to synthesising the evidence. Systematic review has become the highest standard of evidence synthesis. It is well established in the pipeline from research to practice in several fields including health , the environment and social policy . Rigorous systematic reviews are vital for decision-making because they help to provide the strongest evidence that a policy is likely to work (or not). They also help to avoid expensive or dangerous mistakes in the choice of policies.

But systematic review has not yet entirely replaced traditional methods of literature review. These traditional reviews may be susceptible to bias and so may end up providing incorrect conclusions. This is especially worrying when reviews address key policy and practice questions.

The good news is that the limitations of traditional literature review approaches could be improved relatively easily with a few key procedures. Some of these are not prohibitively costly in terms of skill, time or resources. That’s particularly important in African contexts, where resource constraints are a daily reality, but should not compromise the continent’s need for rigorous, systematic and transparent evidence to inform policy.

In our recent paper in Nature Ecology and Evolution , we highlighted eight common problems with traditional literature review methods. We gave examples for each problem, drawing from the field of environmental management and ecology. Finally, we outlined practical solutions.

These are the eight problems we identified in our paper .

First, traditional literature reviews can lack relevance. This is because limited stakeholder engagement can lead to a review that is of limited practical use to decision-makers.

Second, reviews that don’t publish their methods in an a priori (meaning that it is published before the review work begins) protocol may suffer from mission creep. In our paper we give the example of a 2019 review that initially stated it was looking at all population trends among insects. Instead, it ended up focusing only on studies that showed insect population declines. This could have been prevented by publishing and sticking to methods outlined in a protocol.

Third, a lack of transparency and replicability in the review methods may mean that the review cannot be replicated . Replicability is a central tenet of the scientific method.

Selection bias is another common problem. Here, the studies that are included in a literature review are not representative of the evidence base. A lack of comprehensiveness, stemming from an inappropriate search method, can also mean that reviews end up with the wrong evidence for the question at hand.

Traditional reviews may also exclude grey literature . This is defined as any document

produced on all levels of government, academics, business and industry in print and electronic formats, but which is not controlled by commercial publishers, i.e., where publishing is not the primary activity of the producing body.

It includes organisational reports and unpublished theses or other studies . Traditional reviews may also fail to test for evidence of publication bias; both these issues can result in incorrect or misleading conclusions. Another common error is to treat all evidence as equally valid. The reality is that some research studies are more valid than others. This needs to be accounted for in the synthesis.

Inappropriate synthesis is another common issue. This involves methods like vote-counting, which refers to tallying studies based on their statistical significance. Finally, a lack of consistency and error checking (as would happen when a reviewer works alone) can introduce errors and biases if a single reviewer makes decisions without consensus .

All of these common problems can be solved, though. Here’s how.

Stakeholders can be identified, mapped and contacted for feedback and inclusion without the need for extensive budgets. Best-practice guidelines for this process already exist .

Researchers can carefully design and publish an a priori protocol that outlines planned methods for searching, screening, data extraction, critical appraisal and synthesis in detail. Organisations like the Collaboration for Environmental Evidence have existing protocols from which people can draw.

Researchers also need to be explicit and use high-quality guidance and standards for review conduct and reporting . Several such standards already exist .

Another useful approach is to carefully design a search strategy with an info specialist; to trial the search strategy against a benchmark list; and to use multiple bibliographic databases, languages and sources of grey literature. Researchers should then publish their search methods in an a priori protocol for peer review.

Researchers should consider carefully planning and trialling a critical appraisal tool before starting the process in full, learning from existing robust critical appraisal tools . Critical appraisal is the carefully planned assessment of all possible risks of bias and possible confounders in a research study. Researchers should select their synthesis method carefully, based on the data analysed. Vote-counting should never be used instead of meta-analysis. Formal methods for narrative synthesis should be used to summarise and describe the evidence base.

Finally, at least two reviewers should screen a subset of the evidence base to ensure consistency and shared understanding of the methods before proceeding. Ideally, reviewers should conduct all decisions separately and then consolidate.

Collaboration

Collaboration is crucial to address the problems with traditional review processes. Authors need to conduct more rigorous reviews. Editors and peer reviewers need to gate-keep more strictly. The community of methodologists needs to better support the broader research community.

Working together, the academic and research community can build and maintain a strong system of rigorous, evidence-informed decision-making in conservation and environmental management – and, ultimately, in other disciplines.

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How to Write a Literature Review | Guide, Examples, & Templates

Published on January 2, 2023 by Shona McCombes . Revised on September 11, 2023.

What is a literature review? A literature review is a survey of scholarly sources on a specific topic. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research that you can later apply to your paper, thesis, or dissertation topic .

There are five key steps to writing a literature review:

  • Search for relevant literature
  • Evaluate sources
  • Identify themes, debates, and gaps
  • Outline the structure
  • Write your literature review

A good literature review doesn’t just summarize sources—it analyzes, synthesizes , and critically evaluates to give a clear picture of the state of knowledge on the subject.

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Table of contents

What is the purpose of a literature review, examples of literature reviews, step 1 – search for relevant literature, step 2 – evaluate and select sources, step 3 – identify themes, debates, and gaps, step 4 – outline your literature review’s structure, step 5 – write your literature review, free lecture slides, other interesting articles, frequently asked questions, introduction.

  • Quick Run-through
  • Step 1 & 2

When you write a thesis , dissertation , or research paper , you will likely have to conduct a literature review to situate your research within existing knowledge. The literature review gives you a chance to:

  • Demonstrate your familiarity with the topic and its scholarly context
  • Develop a theoretical framework and methodology for your research
  • Position your work in relation to other researchers and theorists
  • Show how your research addresses a gap or contributes to a debate
  • Evaluate the current state of research and demonstrate your knowledge of the scholarly debates around your topic.

Writing literature reviews is a particularly important skill if you want to apply for graduate school or pursue a career in research. We’ve written a step-by-step guide that you can follow below.

Literature review guide

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Writing literature reviews can be quite challenging! A good starting point could be to look at some examples, depending on what kind of literature review you’d like to write.

  • Example literature review #1: “Why Do People Migrate? A Review of the Theoretical Literature” ( Theoretical literature review about the development of economic migration theory from the 1950s to today.)
  • Example literature review #2: “Literature review as a research methodology: An overview and guidelines” ( Methodological literature review about interdisciplinary knowledge acquisition and production.)
  • Example literature review #3: “The Use of Technology in English Language Learning: A Literature Review” ( Thematic literature review about the effects of technology on language acquisition.)
  • Example literature review #4: “Learners’ Listening Comprehension Difficulties in English Language Learning: A Literature Review” ( Chronological literature review about how the concept of listening skills has changed over time.)

You can also check out our templates with literature review examples and sample outlines at the links below.

Download Word doc Download Google doc

Before you begin searching for literature, you need a clearly defined topic .

If you are writing the literature review section of a dissertation or research paper, you will search for literature related to your research problem and questions .

Make a list of keywords

Start by creating a list of keywords related to your research question. Include each of the key concepts or variables you’re interested in, and list any synonyms and related terms. You can add to this list as you discover new keywords in the process of your literature search.

  • Social media, Facebook, Instagram, Twitter, Snapchat, TikTok
  • Body image, self-perception, self-esteem, mental health
  • Generation Z, teenagers, adolescents, youth

Search for relevant sources

Use your keywords to begin searching for sources. Some useful databases to search for journals and articles include:

  • Your university’s library catalogue
  • Google Scholar
  • Project Muse (humanities and social sciences)
  • Medline (life sciences and biomedicine)
  • EconLit (economics)
  • Inspec (physics, engineering and computer science)

You can also use boolean operators to help narrow down your search.

Make sure to read the abstract to find out whether an article is relevant to your question. When you find a useful book or article, you can check the bibliography to find other relevant sources.

You likely won’t be able to read absolutely everything that has been written on your topic, so it will be necessary to evaluate which sources are most relevant to your research question.

For each publication, ask yourself:

  • What question or problem is the author addressing?
  • What are the key concepts and how are they defined?
  • What are the key theories, models, and methods?
  • Does the research use established frameworks or take an innovative approach?
  • What are the results and conclusions of the study?
  • How does the publication relate to other literature in the field? Does it confirm, add to, or challenge established knowledge?
  • What are the strengths and weaknesses of the research?

Make sure the sources you use are credible , and make sure you read any landmark studies and major theories in your field of research.

You can use our template to summarize and evaluate sources you’re thinking about using. Click on either button below to download.

Take notes and cite your sources

As you read, you should also begin the writing process. Take notes that you can later incorporate into the text of your literature review.

It is important to keep track of your sources with citations to avoid plagiarism . It can be helpful to make an annotated bibliography , where you compile full citation information and write a paragraph of summary and analysis for each source. This helps you remember what you read and saves time later in the process.

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To begin organizing your literature review’s argument and structure, be sure you understand the connections and relationships between the sources you’ve read. Based on your reading and notes, you can look for:

  • Trends and patterns (in theory, method or results): do certain approaches become more or less popular over time?
  • Themes: what questions or concepts recur across the literature?
  • Debates, conflicts and contradictions: where do sources disagree?
  • Pivotal publications: are there any influential theories or studies that changed the direction of the field?
  • Gaps: what is missing from the literature? Are there weaknesses that need to be addressed?

This step will help you work out the structure of your literature review and (if applicable) show how your own research will contribute to existing knowledge.

  • Most research has focused on young women.
  • There is an increasing interest in the visual aspects of social media.
  • But there is still a lack of robust research on highly visual platforms like Instagram and Snapchat—this is a gap that you could address in your own research.

There are various approaches to organizing the body of a literature review. Depending on the length of your literature review, you can combine several of these strategies (for example, your overall structure might be thematic, but each theme is discussed chronologically).

Chronological

The simplest approach is to trace the development of the topic over time. However, if you choose this strategy, be careful to avoid simply listing and summarizing sources in order.

Try to analyze patterns, turning points and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred.

If you have found some recurring central themes, you can organize your literature review into subsections that address different aspects of the topic.

For example, if you are reviewing literature about inequalities in migrant health outcomes, key themes might include healthcare policy, language barriers, cultural attitudes, legal status, and economic access.

Methodological

If you draw your sources from different disciplines or fields that use a variety of research methods , you might want to compare the results and conclusions that emerge from different approaches. For example:

  • Look at what results have emerged in qualitative versus quantitative research
  • Discuss how the topic has been approached by empirical versus theoretical scholarship
  • Divide the literature into sociological, historical, and cultural sources

Theoretical

A literature review is often the foundation for a theoretical framework . You can use it to discuss various theories, models, and definitions of key concepts.

You might argue for the relevance of a specific theoretical approach, or combine various theoretical concepts to create a framework for your research.

Like any other academic text , your literature review should have an introduction , a main body, and a conclusion . What you include in each depends on the objective of your literature review.

The introduction should clearly establish the focus and purpose of the literature review.

Depending on the length of your literature review, you might want to divide the body into subsections. You can use a subheading for each theme, time period, or methodological approach.

As you write, you can follow these tips:

  • Summarize and synthesize: give an overview of the main points of each source and combine them into a coherent whole
  • Analyze and interpret: don’t just paraphrase other researchers — add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
  • Critically evaluate: mention the strengths and weaknesses of your sources
  • Write in well-structured paragraphs: use transition words and topic sentences to draw connections, comparisons and contrasts

In the conclusion, you should summarize the key findings you have taken from the literature and emphasize their significance.

When you’ve finished writing and revising your literature review, don’t forget to proofread thoroughly before submitting. Not a language expert? Check out Scribbr’s professional proofreading services !

This article has been adapted into lecture slides that you can use to teach your students about writing a literature review.

Scribbr slides are free to use, customize, and distribute for educational purposes.

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If you want to know more about the research process , methodology , research bias , or statistics , make sure to check out some of our other articles with explanations and examples.

  • Sampling methods
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  • Stratified sampling
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  • Likert scales
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A literature review is a survey of scholarly sources (such as books, journal articles, and theses) related to a specific topic or research question .

It is often written as part of a thesis, dissertation , or research paper , in order to situate your work in relation to existing knowledge.

There are several reasons to conduct a literature review at the beginning of a research project:

  • To familiarize yourself with the current state of knowledge on your topic
  • To ensure that you’re not just repeating what others have already done
  • To identify gaps in knowledge and unresolved problems that your research can address
  • To develop your theoretical framework and methodology
  • To provide an overview of the key findings and debates on the topic

Writing the literature review shows your reader how your work relates to existing research and what new insights it will contribute.

The literature review usually comes near the beginning of your thesis or dissertation . After the introduction , it grounds your research in a scholarly field and leads directly to your theoretical framework or methodology .

A literature review is a survey of credible sources on a topic, often used in dissertations , theses, and research papers . Literature reviews give an overview of knowledge on a subject, helping you identify relevant theories and methods, as well as gaps in existing research. Literature reviews are set up similarly to other  academic texts , with an introduction , a main body, and a conclusion .

An  annotated bibliography is a list of  source references that has a short description (called an annotation ) for each of the sources. It is often assigned as part of the research process for a  paper .  

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Literature Reviews

  • What is a literature review?
  • Steps in the Literature Review Process
  • Define your research question
  • Determine inclusion and exclusion criteria
  • Choose databases and search
  • Review Results
  • Synthesize Results
  • Analyze Results
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What is a Literature Review?

A literature or narrative review is a comprehensive review and analysis of the published literature on a specific topic or research question. The literature that is reviewed contains: books, articles, academic articles, conference proceedings, association papers, and dissertations. It contains the most pertinent studies and points to important past and current research and practices. It provides background and context, and shows how your research will contribute to the field. 

A literature review should: 

  • Provide a comprehensive and updated review of the literature;
  • Explain why this review has taken place;
  • Articulate a position or hypothesis;
  • Acknowledge and account for conflicting and corroborating points of view

From  S age Research Methods

Purpose of a Literature Review

A literature review can be written as an introduction to a study to:

  • Demonstrate how a study fills a gap in research
  • Compare a study with other research that's been done

Or it can be a separate work (a research article on its own) which:

  • Organizes or describes a topic
  • Describes variables within a particular issue/problem

Limitations of a Literature Review

Some of the limitations of a literature review are:

  • It's a snapshot in time. Unlike other reviews, this one has beginning, a middle and an end. There may be future developments that could make your work less relevant.
  • It may be too focused. Some niche studies may miss the bigger picture.
  • It can be difficult to be comprehensive. There is no way to make sure all the literature on a topic was considered.
  • It is easy to be biased if you stick to top tier journals. There may be other places where people are publishing exemplary research. Look to open access publications and conferences to reflect a more inclusive collection. Also, make sure to include opposing views (and not just supporting evidence).

Source: Grant, Maria J., and Andrew Booth. “A Typology of Reviews: An Analysis of 14 Review Types and Associated Methodologies.” Health Information & Libraries Journal, vol. 26, no. 2, June 2009, pp. 91–108. Wiley Online Library, doi:10.1111/j.1471-1842.2009.00848.x.

Meryl Brodsky : Communication and Information Studies

Hannah Chapman Tripp : Biology, Neuroscience

Carolyn Cunningham : Human Development & Family Sciences, Psychology, Sociology

Larayne Dallas : Engineering

Janelle Hedstrom : Special Education, Curriculum & Instruction, Ed Leadership & Policy ​

Susan Macicak : Linguistics

Imelda Vetter : Dell Medical School

For help in other subject areas, please see the guide to library specialists by subject .

Periodically, UT Libraries runs a workshop covering the basics and library support for literature reviews. While we try to offer these once per academic year, we find providing the recording to be helpful to community members who have missed the session. Following is the most recent recording of the workshop, Conducting a Literature Review. To view the recording, a UT login is required.

  • October 26, 2022 recording
  • Last Updated: Oct 26, 2022 2:49 PM
  • URL: https://guides.lib.utexas.edu/literaturereviews

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  • Published: 12 October 2020

Eight problems with literature reviews and how to fix them

  • Neal R. Haddaway   ORCID: orcid.org/0000-0003-3902-2234 1 , 2 , 3 ,
  • Alison Bethel 4 ,
  • Lynn V. Dicks 5 , 6 ,
  • Julia Koricheva   ORCID: orcid.org/0000-0002-9033-0171 7 ,
  • Biljana Macura   ORCID: orcid.org/0000-0002-4253-1390 2 ,
  • Gillian Petrokofsky 8 ,
  • Andrew S. Pullin 9 ,
  • Sini Savilaakso   ORCID: orcid.org/0000-0002-8514-8105 10 , 11 &
  • Gavin B. Stewart   ORCID: orcid.org/0000-0001-5684-1544 12  

Nature Ecology & Evolution volume  4 ,  pages 1582–1589 ( 2020 ) Cite this article

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An Author Correction to this article was published on 19 October 2020

This article has been updated

Traditional approaches to reviewing literature may be susceptible to bias and result in incorrect decisions. This is of particular concern when reviews address policy- and practice-relevant questions. Systematic reviews have been introduced as a more rigorous approach to synthesizing evidence across studies; they rely on a suite of evidence-based methods aimed at maximizing rigour and minimizing susceptibility to bias. Despite the increasing popularity of systematic reviews in the environmental field, evidence synthesis methods continue to be poorly applied in practice, resulting in the publication of syntheses that are highly susceptible to bias. Recognizing the constraints that researchers can sometimes feel when attempting to plan, conduct and publish rigorous and comprehensive evidence syntheses, we aim here to identify major pitfalls in the conduct and reporting of systematic reviews, making use of recent examples from across the field. Adopting a ‘critical friend’ role in supporting would-be systematic reviews and avoiding individual responses to police use of the ‘systematic review’ label, we go on to identify methodological solutions to mitigate these pitfalls. We then highlight existing support available to avoid these issues and call on the entire community, including systematic review specialists, to work towards better evidence syntheses for better evidence and better decisions.

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limitations in literature review

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Acknowledgements

We thank C. Shortall from Rothamstead Research for useful discussions on the topic.

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Neal R. Haddaway

Stockholm Environment Institute, Stockholm, Sweden

Neal R. Haddaway & Biljana Macura

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Alison Bethel

Department of Zoology, University of Cambridge, Cambridge, UK

Lynn V. Dicks

School of Biological Sciences, University of East Anglia, Norwich, UK

Department of Biological Sciences, Royal Holloway University of London, Egham, UK

Julia Koricheva

Department of Zoology, University of Oxford, Oxford, UK

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Sini Savilaakso

Department of Forest Sciences, University of Helsinki, Helsinki, Finland

Evidence Synthesis Lab, School of Natural and Environmental Sciences, University of Newcastle, Newcastle-upon-Tyne, UK

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Haddaway, N.R., Bethel, A., Dicks, L.V. et al. Eight problems with literature reviews and how to fix them. Nat Ecol Evol 4 , 1582–1589 (2020). https://doi.org/10.1038/s41559-020-01295-x

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The limitations of the study are those characteristics of design or methodology that impacted or influenced the interpretation of the findings from your research. Study limitations are the constraints placed on the ability to generalize from the results, to further describe applications to practice, and/or related to the utility of findings that are the result of the ways in which you initially chose to design the study or the method used to establish internal and external validity or the result of unanticipated challenges that emerged during the study.

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67; Theofanidis, Dimitrios and Antigoni Fountouki. "Limitations and Delimitations in the Research Process." Perioperative Nursing 7 (September-December 2018): 155-163. .

Importance of...

Always acknowledge a study's limitations. It is far better that you identify and acknowledge your study’s limitations than to have them pointed out by your professor and have your grade lowered because you appeared to have ignored them or didn't realize they existed.

Keep in mind that acknowledgment of a study's limitations is an opportunity to make suggestions for further research. If you do connect your study's limitations to suggestions for further research, be sure to explain the ways in which these unanswered questions may become more focused because of your study.

Acknowledgment of a study's limitations also provides you with opportunities to demonstrate that you have thought critically about the research problem, understood the relevant literature published about it, and correctly assessed the methods chosen for studying the problem. A key objective of the research process is not only discovering new knowledge but also to confront assumptions and explore what we don't know.

Claiming limitations is a subjective process because you must evaluate the impact of those limitations . Don't just list key weaknesses and the magnitude of a study's limitations. To do so diminishes the validity of your research because it leaves the reader wondering whether, or in what ways, limitation(s) in your study may have impacted the results and conclusions. Limitations require a critical, overall appraisal and interpretation of their impact. You should answer the question: do these problems with errors, methods, validity, etc. eventually matter and, if so, to what extent?

Price, James H. and Judy Murnan. “Research Limitations and the Necessity of Reporting Them.” American Journal of Health Education 35 (2004): 66-67; Structure: How to Structure the Research Limitations Section of Your Dissertation. Dissertations and Theses: An Online Textbook. Laerd.com.

Descriptions of Possible Limitations

All studies have limitations . However, it is important that you restrict your discussion to limitations related to the research problem under investigation. For example, if a meta-analysis of existing literature is not a stated purpose of your research, it should not be discussed as a limitation. Do not apologize for not addressing issues that you did not promise to investigate in the introduction of your paper.

Here are examples of limitations related to methodology and the research process you may need to describe and discuss how they possibly impacted your results. Note that descriptions of limitations should be stated in the past tense because they were discovered after you completed your research.

Possible Methodological Limitations

  • Sample size -- the number of the units of analysis you use in your study is dictated by the type of research problem you are investigating. Note that, if your sample size is too small, it will be difficult to find significant relationships from the data, as statistical tests normally require a larger sample size to ensure a representative distribution of the population and to be considered representative of groups of people to whom results will be generalized or transferred. Note that sample size is generally less relevant in qualitative research if explained in the context of the research problem.
  • Lack of available and/or reliable data -- a lack of data or of reliable data will likely require you to limit the scope of your analysis, the size of your sample, or it can be a significant obstacle in finding a trend and a meaningful relationship. You need to not only describe these limitations but provide cogent reasons why you believe data is missing or is unreliable. However, don’t just throw up your hands in frustration; use this as an opportunity to describe a need for future research based on designing a different method for gathering data.
  • Lack of prior research studies on the topic -- citing prior research studies forms the basis of your literature review and helps lay a foundation for understanding the research problem you are investigating. Depending on the currency or scope of your research topic, there may be little, if any, prior research on your topic. Before assuming this to be true, though, consult with a librarian! In cases when a librarian has confirmed that there is little or no prior research, you may be required to develop an entirely new research typology [for example, using an exploratory rather than an explanatory research design ]. Note again that discovering a limitation can serve as an important opportunity to identify new gaps in the literature and to describe the need for further research.
  • Measure used to collect the data -- sometimes it is the case that, after completing your interpretation of the findings, you discover that the way in which you gathered data inhibited your ability to conduct a thorough analysis of the results. For example, you regret not including a specific question in a survey that, in retrospect, could have helped address a particular issue that emerged later in the study. Acknowledge the deficiency by stating a need for future researchers to revise the specific method for gathering data.
  • Self-reported data -- whether you are relying on pre-existing data or you are conducting a qualitative research study and gathering the data yourself, self-reported data is limited by the fact that it rarely can be independently verified. In other words, you have to the accuracy of what people say, whether in interviews, focus groups, or on questionnaires, at face value. However, self-reported data can contain several potential sources of bias that you should be alert to and note as limitations. These biases become apparent if they are incongruent with data from other sources. These are: (1) selective memory [remembering or not remembering experiences or events that occurred at some point in the past]; (2) telescoping [recalling events that occurred at one time as if they occurred at another time]; (3) attribution [the act of attributing positive events and outcomes to one's own agency, but attributing negative events and outcomes to external forces]; and, (4) exaggeration [the act of representing outcomes or embellishing events as more significant than is actually suggested from other data].

Possible Limitations of the Researcher

  • Access -- if your study depends on having access to people, organizations, data, or documents and, for whatever reason, access is denied or limited in some way, the reasons for this needs to be described. Also, include an explanation why being denied or limited access did not prevent you from following through on your study.
  • Longitudinal effects -- unlike your professor, who can literally devote years [even a lifetime] to studying a single topic, the time available to investigate a research problem and to measure change or stability over time is constrained by the due date of your assignment. Be sure to choose a research problem that does not require an excessive amount of time to complete the literature review, apply the methodology, and gather and interpret the results. If you're unsure whether you can complete your research within the confines of the assignment's due date, talk to your professor.
  • Cultural and other type of bias -- we all have biases, whether we are conscience of them or not. Bias is when a person, place, event, or thing is viewed or shown in a consistently inaccurate way. Bias is usually negative, though one can have a positive bias as well, especially if that bias reflects your reliance on research that only support your hypothesis. When proof-reading your paper, be especially critical in reviewing how you have stated a problem, selected the data to be studied, what may have been omitted, the manner in which you have ordered events, people, or places, how you have chosen to represent a person, place, or thing, to name a phenomenon, or to use possible words with a positive or negative connotation. NOTE :   If you detect bias in prior research, it must be acknowledged and you should explain what measures were taken to avoid perpetuating that bias. For example, if a previous study only used boys to examine how music education supports effective math skills, describe how your research expands the study to include girls.
  • Fluency in a language -- if your research focuses , for example, on measuring the perceived value of after-school tutoring among Mexican-American ESL [English as a Second Language] students and you are not fluent in Spanish, you are limited in being able to read and interpret Spanish language research studies on the topic or to speak with these students in their primary language. This deficiency should be acknowledged.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Senunyeme, Emmanuel K. Business Research Methods. Powerpoint Presentation. Regent University of Science and Technology; ter Riet, Gerben et al. “All That Glitters Isn't Gold: A Survey on Acknowledgment of Limitations in Biomedical Studies.” PLOS One 8 (November 2013): 1-6.

Structure and Writing Style

Information about the limitations of your study are generally placed either at the beginning of the discussion section of your paper so the reader knows and understands the limitations before reading the rest of your analysis of the findings, or, the limitations are outlined at the conclusion of the discussion section as an acknowledgement of the need for further study. Statements about a study's limitations should not be buried in the body [middle] of the discussion section unless a limitation is specific to something covered in that part of the paper. If this is the case, though, the limitation should be reiterated at the conclusion of the section.

If you determine that your study is seriously flawed due to important limitations , such as, an inability to acquire critical data, consider reframing it as an exploratory study intended to lay the groundwork for a more complete research study in the future. Be sure, though, to specifically explain the ways that these flaws can be successfully overcome in a new study.

But, do not use this as an excuse for not developing a thorough research paper! Review the tab in this guide for developing a research topic . If serious limitations exist, it generally indicates a likelihood that your research problem is too narrowly defined or that the issue or event under study is too recent and, thus, very little research has been written about it. If serious limitations do emerge, consult with your professor about possible ways to overcome them or how to revise your study.

When discussing the limitations of your research, be sure to:

  • Describe each limitation in detailed but concise terms;
  • Explain why each limitation exists;
  • Provide the reasons why each limitation could not be overcome using the method(s) chosen to acquire or gather the data [cite to other studies that had similar problems when possible];
  • Assess the impact of each limitation in relation to the overall findings and conclusions of your study; and,
  • If appropriate, describe how these limitations could point to the need for further research.

Remember that the method you chose may be the source of a significant limitation that has emerged during your interpretation of the results [for example, you didn't interview a group of people that you later wish you had]. If this is the case, don't panic. Acknowledge it, and explain how applying a different or more robust methodology might address the research problem more effectively in a future study. A underlying goal of scholarly research is not only to show what works, but to demonstrate what doesn't work or what needs further clarification.

Aguinis, Hermam and Jeffrey R. Edwards. “Methodological Wishes for the Next Decade and How to Make Wishes Come True.” Journal of Management Studies 51 (January 2014): 143-174; Brutus, Stéphane et al. "Self-Reported Limitations and Future Directions in Scholarly Reports: Analysis and Recommendations." Journal of Management 39 (January 2013): 48-75; Ioannidis, John P.A. "Limitations are not Properly Acknowledged in the Scientific Literature." Journal of Clinical Epidemiology 60 (2007): 324-329; Pasek, Josh. Writing the Empirical Social Science Research Paper: A Guide for the Perplexed. January 24, 2012. Academia.edu; Structure: How to Structure the Research Limitations Section of Your Dissertation. Dissertations and Theses: An Online Textbook. Laerd.com; What Is an Academic Paper? Institute for Writing Rhetoric. Dartmouth College; Writing the Experimental Report: Methods, Results, and Discussion. The Writing Lab and The OWL. Purdue University.

Writing Tip

Don't Inflate the Importance of Your Findings!

After all the hard work and long hours devoted to writing your research paper, it is easy to get carried away with attributing unwarranted importance to what you’ve done. We all want our academic work to be viewed as excellent and worthy of a good grade, but it is important that you understand and openly acknowledge the limitations of your study. Inflating the importance of your study's findings could be perceived by your readers as an attempt hide its flaws or encourage a biased interpretation of the results. A small measure of humility goes a long way!

Another Writing Tip

Negative Results are Not a Limitation!

Negative evidence refers to findings that unexpectedly challenge rather than support your hypothesis. If you didn't get the results you anticipated, it may mean your hypothesis was incorrect and needs to be reformulated. Or, perhaps you have stumbled onto something unexpected that warrants further study. Moreover, the absence of an effect may be very telling in many situations, particularly in experimental research designs. In any case, your results may very well be of importance to others even though they did not support your hypothesis. Do not fall into the trap of thinking that results contrary to what you expected is a limitation to your study. If you carried out the research well, they are simply your results and only require additional interpretation.

Lewis, George H. and Jonathan F. Lewis. “The Dog in the Night-Time: Negative Evidence in Social Research.” The British Journal of Sociology 31 (December 1980): 544-558.

Yet Another Writing Tip

Sample Size Limitations in Qualitative Research

Sample sizes are typically smaller in qualitative research because, as the study goes on, acquiring more data does not necessarily lead to more information. This is because one occurrence of a piece of data, or a code, is all that is necessary to ensure that it becomes part of the analysis framework. However, it remains true that sample sizes that are too small cannot adequately support claims of having achieved valid conclusions and sample sizes that are too large do not permit the deep, naturalistic, and inductive analysis that defines qualitative inquiry. Determining adequate sample size in qualitative research is ultimately a matter of judgment and experience in evaluating the quality of the information collected against the uses to which it will be applied and the particular research method and purposeful sampling strategy employed. If the sample size is found to be a limitation, it may reflect your judgment about the methodological technique chosen [e.g., single life history study versus focus group interviews] rather than the number of respondents used.

Boddy, Clive Roland. "Sample Size for Qualitative Research." Qualitative Market Research: An International Journal 19 (2016): 426-432; Huberman, A. Michael and Matthew B. Miles. "Data Management and Analysis Methods." In Handbook of Qualitative Research . Norman K. Denzin and Yvonna S. Lincoln, eds. (Thousand Oaks, CA: Sage, 1994), pp. 428-444; Blaikie, Norman. "Confounding Issues Related to Determining Sample Size in Qualitative Research." International Journal of Social Research Methodology 21 (2018): 635-641; Oppong, Steward Harrison. "The Problem of Sampling in qualitative Research." Asian Journal of Management Sciences and Education 2 (2013): 202-210.

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Advantages and disadvantages of literature review

This comprehensive article explores some of the advantages and disadvantages of literature review in research. Reviewing relevant literature is a key area in research, and indeed, it is a research activity in itself. It helps researchers investigate a particular topic in detail. However, it has some limitations as well.

What is literature review?

In order to understand the advantages and disadvantages of literature review, it is important to understand what a literature review is and how it differs from other methods of research. According to Jones and Gratton (2009) a literature review essentially consists of critically reading, evaluating, and organising existing literature on a topic to assess the state of knowledge in the area. It is sometimes called critical review.

A literature review is a select analysis of existing research which is relevant to a researcher’s selected topic, showing how it relates to their investigation. It explains and justifies how their investigation may help answer some of the questions or gaps in the chosen area of study (University of Reading, 2022).

A literature review is a term used in the field of research to describe a systematic and methodical investigation of the relevant literature on a particular topic. In other words, it is an analysis of existing research on a topic in order to identify any relevant studies and draw conclusions about the topic.

A literature review is not the same as a bibliography or a database search. Rather than simply listing references to sources of information, a literature review involves critically evaluating and summarizing existing research on a topic. As such, it is a much more detailed and complex process than simply searching databases and websites, and it requires a lot of effort and skills.

Advantages of literature review

Information synthesis

A literature review is a very thorough and methodical exercise. It can be used to synthesize information and draw conclusions about a particular topic. Through a careful evaluation and critical summarization, researchers can draw a clear and comprehensive picture of the chosen topic.

Familiarity with the current knowledge

According to the University of Illinois (2022), literature reviews allow researchers to gain familiarity with the existing knowledge in their selected field, as well as the boundaries and limitations of that field.

Creation of new body of knowledge

One of the key advantages of literature review is that it creates new body of knowledge. Through careful evaluation and critical summarisation, researchers can create a new body of knowledge and enrich the field of study.

Answers to a range of questions

Literature reviews help researchers analyse the existing body of knowledge to determine the answers to a range of questions concerning a particular subject.

Disadvantages of literature review

Time consuming

As a literature review involves collecting and evaluating research and summarizing the findings, it requires a significant amount of time. To conduct a comprehensive review, researchers need to read many different articles and analyse a lot of data. This means that their review will take a long time to complete.

Lack of quality sources  

Researchers are expected to use a wide variety of sources of information to present a comprehensive review. However, it may sometimes be challenging for them to identify the quality sources because of the availability of huge numbers in their chosen field. It may also happen because of the lack of past empirical work, particularly if the selected topic is an unpopular one.

Descriptive writing

One of the major disadvantages of literature review is that instead of critical appreciation, some researchers end up developing reviews that are mostly descriptive. Their reviews are often more like summaries of the work of other writers and lack in criticality. It is worth noting that they must go beyond describing the literature.

Key features of literature review

Clear organisation

A literature review is typically a very critical and thorough process. Universities usually recommend students a particular structure to develop their reviews. Like all other academic writings, a review starts with an introduction and ends with a conclusion. Between the beginning and the end, researchers present the main body of the review containing the critical discussion of sources.

No obvious bias

A key feature of a literature review is that it should be very unbiased and objective. However, it should be mentioned that researchers may sometimes be influenced by their own opinions of the world.

Proper citation

One of the key features of literature review is that it must be properly cited. Researchers should include all the sources that they have used for information. They must do citations and provide a reference list by the end in line with a recognized referencing system such as Harvard.

To conclude this article, it can be said that a literature review is a type of research that seeks to examine and summarise existing research on a particular topic. It is an essential part of a dissertation/thesis. However, it is not an easy thing to handle by an inexperienced person. It also requires a lot of time and patience.

Hope you like this ‘Advantages and disadvantages of literature review’. Please share this with others to support our research work.

Other useful articles:

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Last update: 08 May 2022

References:

Jones, I., & Gratton, C. (2009) Research Methods for Sports Shttps://www.howandwhat.net/new/evaluate-website-content/tudies, 2 nd edition, London: Routledge

University of Illinois (2022) Literature review, available at: https://www.uis.edu/learning-hub/writing-resources/handouts/learning-hub/literature-review (accessed 08 May 2022)

University of Reading (2022) Literature reviews, available at: https://libguides.reading.ac.uk/literaturereview/starting (accessed 07 May 2022)

Author: M Rahman

M Rahman writes extensively online and offline with an emphasis on business management, marketing, and tourism. He is a lecturer in Management and Marketing. He holds an MSc in Tourism & Hospitality from the University of Sunderland. Also, graduated from Leeds Metropolitan University with a BA in Business & Management Studies and completed a DTLLS (Diploma in Teaching in the Life-Long Learning Sector) from London South Bank University.

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Writing a Literature Review

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A literature review is a document or section of a document that collects key sources on a topic and discusses those sources in conversation with each other (also called synthesis ). The lit review is an important genre in many disciplines, not just literature (i.e., the study of works of literature such as novels and plays). When we say “literature review” or refer to “the literature,” we are talking about the research ( scholarship ) in a given field. You will often see the terms “the research,” “the scholarship,” and “the literature” used mostly interchangeably.

Where, when, and why would I write a lit review?

There are a number of different situations where you might write a literature review, each with slightly different expectations; different disciplines, too, have field-specific expectations for what a literature review is and does. For instance, in the humanities, authors might include more overt argumentation and interpretation of source material in their literature reviews, whereas in the sciences, authors are more likely to report study designs and results in their literature reviews; these differences reflect these disciplines’ purposes and conventions in scholarship. You should always look at examples from your own discipline and talk to professors or mentors in your field to be sure you understand your discipline’s conventions, for literature reviews as well as for any other genre.

A literature review can be a part of a research paper or scholarly article, usually falling after the introduction and before the research methods sections. In these cases, the lit review just needs to cover scholarship that is important to the issue you are writing about; sometimes it will also cover key sources that informed your research methodology.

Lit reviews can also be standalone pieces, either as assignments in a class or as publications. In a class, a lit review may be assigned to help students familiarize themselves with a topic and with scholarship in their field, get an idea of the other researchers working on the topic they’re interested in, find gaps in existing research in order to propose new projects, and/or develop a theoretical framework and methodology for later research. As a publication, a lit review usually is meant to help make other scholars’ lives easier by collecting and summarizing, synthesizing, and analyzing existing research on a topic. This can be especially helpful for students or scholars getting into a new research area, or for directing an entire community of scholars toward questions that have not yet been answered.

What are the parts of a lit review?

Most lit reviews use a basic introduction-body-conclusion structure; if your lit review is part of a larger paper, the introduction and conclusion pieces may be just a few sentences while you focus most of your attention on the body. If your lit review is a standalone piece, the introduction and conclusion take up more space and give you a place to discuss your goals, research methods, and conclusions separately from where you discuss the literature itself.

Introduction:

  • An introductory paragraph that explains what your working topic and thesis is
  • A forecast of key topics or texts that will appear in the review
  • Potentially, a description of how you found sources and how you analyzed them for inclusion and discussion in the review (more often found in published, standalone literature reviews than in lit review sections in an article or research paper)
  • Summarize and synthesize: Give an overview of the main points of each source and combine them into a coherent whole
  • Analyze and interpret: Don’t just paraphrase other researchers – add your own interpretations where possible, discussing the significance of findings in relation to the literature as a whole
  • Critically Evaluate: Mention the strengths and weaknesses of your sources
  • Write in well-structured paragraphs: Use transition words and topic sentence to draw connections, comparisons, and contrasts.

Conclusion:

  • Summarize the key findings you have taken from the literature and emphasize their significance
  • Connect it back to your primary research question

How should I organize my lit review?

Lit reviews can take many different organizational patterns depending on what you are trying to accomplish with the review. Here are some examples:

  • Chronological : The simplest approach is to trace the development of the topic over time, which helps familiarize the audience with the topic (for instance if you are introducing something that is not commonly known in your field). If you choose this strategy, be careful to avoid simply listing and summarizing sources in order. Try to analyze the patterns, turning points, and key debates that have shaped the direction of the field. Give your interpretation of how and why certain developments occurred (as mentioned previously, this may not be appropriate in your discipline — check with a teacher or mentor if you’re unsure).
  • Thematic : If you have found some recurring central themes that you will continue working with throughout your piece, you can organize your literature review into subsections that address different aspects of the topic. For example, if you are reviewing literature about women and religion, key themes can include the role of women in churches and the religious attitude towards women.
  • Qualitative versus quantitative research
  • Empirical versus theoretical scholarship
  • Divide the research by sociological, historical, or cultural sources
  • Theoretical : In many humanities articles, the literature review is the foundation for the theoretical framework. You can use it to discuss various theories, models, and definitions of key concepts. You can argue for the relevance of a specific theoretical approach or combine various theorical concepts to create a framework for your research.

What are some strategies or tips I can use while writing my lit review?

Any lit review is only as good as the research it discusses; make sure your sources are well-chosen and your research is thorough. Don’t be afraid to do more research if you discover a new thread as you’re writing. More info on the research process is available in our "Conducting Research" resources .

As you’re doing your research, create an annotated bibliography ( see our page on the this type of document ). Much of the information used in an annotated bibliography can be used also in a literature review, so you’ll be not only partially drafting your lit review as you research, but also developing your sense of the larger conversation going on among scholars, professionals, and any other stakeholders in your topic.

Usually you will need to synthesize research rather than just summarizing it. This means drawing connections between sources to create a picture of the scholarly conversation on a topic over time. Many student writers struggle to synthesize because they feel they don’t have anything to add to the scholars they are citing; here are some strategies to help you:

  • It often helps to remember that the point of these kinds of syntheses is to show your readers how you understand your research, to help them read the rest of your paper.
  • Writing teachers often say synthesis is like hosting a dinner party: imagine all your sources are together in a room, discussing your topic. What are they saying to each other?
  • Look at the in-text citations in each paragraph. Are you citing just one source for each paragraph? This usually indicates summary only. When you have multiple sources cited in a paragraph, you are more likely to be synthesizing them (not always, but often
  • Read more about synthesis here.

The most interesting literature reviews are often written as arguments (again, as mentioned at the beginning of the page, this is discipline-specific and doesn’t work for all situations). Often, the literature review is where you can establish your research as filling a particular gap or as relevant in a particular way. You have some chance to do this in your introduction in an article, but the literature review section gives a more extended opportunity to establish the conversation in the way you would like your readers to see it. You can choose the intellectual lineage you would like to be part of and whose definitions matter most to your thinking (mostly humanities-specific, but this goes for sciences as well). In addressing these points, you argue for your place in the conversation, which tends to make the lit review more compelling than a simple reporting of other sources.

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Writing a Literature Review

Phase 1: scope of review, it's a literature review of what, precisely.

Need to Have a Precise Topic It is essential that one defines a research topic very carefully. For example, it should not be too far-reaching. The following is much too broad:

"Life and Times of Sigmund Freud"

However, this is more focused and specific and, accordingly, a more appropriate topic:

"An Analysis of the Relationship of Freud and Jung in the International Psychoanalytic Association, 1910-1914"

Limitations of Study In specifying precisely one's research topic, one is also specifying appropriate limitations on the research. Limiting, for example, by time, personnel, gender, age, location, nationality, etc. results in a more focused and meaningful topic.  

Scope of the Literature Review It is also important to determine the precise scope of the literature review. For example,

  • What exactly will you cover in your review?
  • How comprehensive will it be?
  • How long? About how many citations will you use?
  • How detailed? Will it be a review of ALL relevant material or will the scope be limited to more recent material, e.g., the last five years.
  • Are you focusing on methodological approaches; on theoretical issues; on qualitative or quantitative research?
  • Will you broaden your search to seek literature in related disciplines?
  • Will you confine your reviewed material to English language only or will you include research in other languages too?

In evaluating studies, timeliness is more significant for some subjects than others. Scientists generally need more recent material. However, currency is often less of a factor for scholars in arts/humanities. Research published in 1920 about Plato's philosophy might be more relevant than recent studies.

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  • Tags: literature_review , literature_review_in_education

Limitations of the literature – A guide to a sticky problem

limitations in literature review

One of the more difficult tasks set for a Masters and especially PhD student is to identify limitations in the literature under review. Postgraduate students are required not only to “tell” (repeat what an author/s say) but to critically engage the literature being reviewed. This work typically appears in a separate chapter in the thesis or dissertation under the title Literature Review. To help you, here are 10 typical examples often used to identify limitations in a particular body of literature—with a caveat—using education examples.

1. The sample size is too small and therefore not representative of the phenomenon being studied This is fine but be aware of the fact that a single case study (e.g. the leadership practices of a non-traditional principal) is completely acceptable in a qualitative study. Here depth makes up for spread (representivity) for the purpose of the study is different e.g. an ethnographic case study of one principal.

2. The context is limiting and therefore not representative of all  This too is acceptable e.g. a study of subject competency levels of 10 science teachers in rural Limpopo province. However, always specific WHAT it is about the context that is limiting e.g. nothing about science teachers in urban areas. A common mistake is to say ‘that study was done in America’ but that is not helpful in itself. What is it about the American context that might not be applicable in the Southern African context?

3. The study is dated as in out-of-date e.g. 1985 This is important as a criticism except in the case of historical studies or in reference to a classical piece of work that set the standard for understanding a particular problem. For example, Michael Apple’s 1979 Ideology and Curriculum might be dated but it is the landmark criticism in the politics of curriculum and often deserves referencing as a launching pad for more recent studies.

4. The period of observation was too short This is valuable especially in the qualitative study of classrooms where the researcher visits a history class of 10 teachers once and then jumps to make major findings and conclusions from a 40-minute lesson per teacher. This is a common problem with qualitative research in education in South Africa—the lack of extended engagement in the field.

5. The theoretical framework or theory is limiting A researcher might be using a particular theory to explain events e.g. a behaviorist account of learner discipline where you believe that a constructivist account offers more insight into why learners misbehave in classrooms. The onus is still on you to explain why the rival theory is ‘better’ than the one used.

6. The methodological approach is inappropriate for the question posed A study uses a self-reporting questionnaire completed by teachers to determine their competency levels in mathematics teaching. You could argue that direct observation of actual teaching is a much more direct measure of teaching competency in mathematics since teachers might overestimate their own levels of competency in the subject (by the way, there is research to back you up with such a claim)

7. The research question or instrument(s) is biased A study that asks ‘why teachers are incompetent’ or ‘the students are lazy’ already assumes the fact ahead of the inquiry itself. The research question can and should be posed in an open-ended manner to allow for more than one outcome. In the controversial SU study on Coloured women’s cognitive abilities and health styles it was found that the measuring instrument used was found in other studies to be flawed. And the study of code-switching in a Grade 6 language classroom would clearly show bias if the researcher was competent in English alone—unless, of course, this deficiency is remedied in the study design.

8. The study does not differentiate between subjects or contexts A report might give the results of a study for academic performance in Grade 12 economics in the National Senior Certificate, which is fine, but does not differentiate between the results of the former white schools and those of black schools thereby concealing variable performance and, for the sake of reform, where exactly added support might be needed.

9. The literature reviewed does not cover the subject at all or from a particular perspective The conclusion that ‘there is no research on topic X’ is a common one among students and often wrong. The fact that you have not yet found literature on topic X does not mean that such references do not exist. However, there are instances in which the case can and should be made that topic X appears to be understudied given the literature reviewed. Hint: always check with your supervisor and other experts whether the ‘not yet researched’ claim is justified. More plausible are studies which critique a dominant perspective on a subject and offer a new lens on the same issue (see point #5) above.

10. The study is based largely on opinion and uses primarily secondary sources This is a very valid criticism of many articles posing as research studies where the evidence is often anecdotal (not ‘thick descriptions’ as anthropologists like to point out) and drawing on other opinion pieces rather than solid research on the topic.

REMEMBER: THESE NOTES ARE NOT ABOUT HOW TO IDENTIFY LIMITATIONS IN LITERATURE REVIEWED FOR YOUR STUDY. IT IS NOT ABOUT LISTING THE LIMITATIONS OF YOUR STUDY IN THE COURSE OF WRITING UP A RESEARCH PROPOSAL OR THE THESIS ITSELF, EVEN THOUGH THIS COULD HELP YOU DEFEND SELF-IDENTIFIED LIMITATIONS OF YOUR RESEARCH.

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  • http://orcid.org/0000-0003-0157-5319 Ahtisham Younas 1 , 2 ,
  • http://orcid.org/0000-0002-7839-8130 Parveen Ali 3 , 4
  • 1 Memorial University of Newfoundland , St John's , Newfoundland , Canada
  • 2 Swat College of Nursing , Pakistan
  • 3 School of Nursing and Midwifery , University of Sheffield , Sheffield , South Yorkshire , UK
  • 4 Sheffield University Interpersonal Violence Research Group , Sheffield University , Sheffield , UK
  • Correspondence to Ahtisham Younas, Memorial University of Newfoundland, St John's, NL A1C 5C4, Canada; ay6133{at}mun.ca

https://doi.org/10.1136/ebnurs-2021-103417

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Introduction

Literature reviews offer a critical synthesis of empirical and theoretical literature to assess the strength of evidence, develop guidelines for practice and policymaking, and identify areas for future research. 1 It is often essential and usually the first task in any research endeavour, particularly in masters or doctoral level education. For effective data extraction and rigorous synthesis in reviews, the use of literature summary tables is of utmost importance. A literature summary table provides a synopsis of an included article. It succinctly presents its purpose, methods, findings and other relevant information pertinent to the review. The aim of developing these literature summary tables is to provide the reader with the information at one glance. Since there are multiple types of reviews (eg, systematic, integrative, scoping, critical and mixed methods) with distinct purposes and techniques, 2 there could be various approaches for developing literature summary tables making it a complex task specialty for the novice researchers or reviewers. Here, we offer five tips for authors of the review articles, relevant to all types of reviews, for creating useful and relevant literature summary tables. We also provide examples from our published reviews to illustrate how useful literature summary tables can be developed and what sort of information should be provided.

Tip 1: provide detailed information about frameworks and methods

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Tabular literature summaries from a scoping review. Source: Rasheed et al . 3

The provision of information about conceptual and theoretical frameworks and methods is useful for several reasons. First, in quantitative (reviews synthesising the results of quantitative studies) and mixed reviews (reviews synthesising the results of both qualitative and quantitative studies to address a mixed review question), it allows the readers to assess the congruence of the core findings and methods with the adapted framework and tested assumptions. In qualitative reviews (reviews synthesising results of qualitative studies), this information is beneficial for readers to recognise the underlying philosophical and paradigmatic stance of the authors of the included articles. For example, imagine the authors of an article, included in a review, used phenomenological inquiry for their research. In that case, the review authors and the readers of the review need to know what kind of (transcendental or hermeneutic) philosophical stance guided the inquiry. Review authors should, therefore, include the philosophical stance in their literature summary for the particular article. Second, information about frameworks and methods enables review authors and readers to judge the quality of the research, which allows for discerning the strengths and limitations of the article. For example, if authors of an included article intended to develop a new scale and test its psychometric properties. To achieve this aim, they used a convenience sample of 150 participants and performed exploratory (EFA) and confirmatory factor analysis (CFA) on the same sample. Such an approach would indicate a flawed methodology because EFA and CFA should not be conducted on the same sample. The review authors must include this information in their summary table. Omitting this information from a summary could lead to the inclusion of a flawed article in the review, thereby jeopardising the review’s rigour.

Tip 2: include strengths and limitations for each article

Critical appraisal of individual articles included in a review is crucial for increasing the rigour of the review. Despite using various templates for critical appraisal, authors often do not provide detailed information about each reviewed article’s strengths and limitations. Merely noting the quality score based on standardised critical appraisal templates is not adequate because the readers should be able to identify the reasons for assigning a weak or moderate rating. Many recent critical appraisal checklists (eg, Mixed Methods Appraisal Tool) discourage review authors from assigning a quality score and recommend noting the main strengths and limitations of included studies. It is also vital that methodological and conceptual limitations and strengths of the articles included in the review are provided because not all review articles include empirical research papers. Rather some review synthesises the theoretical aspects of articles. Providing information about conceptual limitations is also important for readers to judge the quality of foundations of the research. For example, if you included a mixed-methods study in the review, reporting the methodological and conceptual limitations about ‘integration’ is critical for evaluating the study’s strength. Suppose the authors only collected qualitative and quantitative data and did not state the intent and timing of integration. In that case, the strength of the study is weak. Integration only occurred at the levels of data collection. However, integration may not have occurred at the analysis, interpretation and reporting levels.

Tip 3: write conceptual contribution of each reviewed article

While reading and evaluating review papers, we have observed that many review authors only provide core results of the article included in a review and do not explain the conceptual contribution offered by the included article. We refer to conceptual contribution as a description of how the article’s key results contribute towards the development of potential codes, themes or subthemes, or emerging patterns that are reported as the review findings. For example, the authors of a review article noted that one of the research articles included in their review demonstrated the usefulness of case studies and reflective logs as strategies for fostering compassion in nursing students. The conceptual contribution of this research article could be that experiential learning is one way to teach compassion to nursing students, as supported by case studies and reflective logs. This conceptual contribution of the article should be mentioned in the literature summary table. Delineating each reviewed article’s conceptual contribution is particularly beneficial in qualitative reviews, mixed-methods reviews, and critical reviews that often focus on developing models and describing or explaining various phenomena. Figure 2 offers an example of a literature summary table. 4

Tabular literature summaries from a critical review. Source: Younas and Maddigan. 4

Tip 4: compose potential themes from each article during summary writing

While developing literature summary tables, many authors use themes or subthemes reported in the given articles as the key results of their own review. Such an approach prevents the review authors from understanding the article’s conceptual contribution, developing rigorous synthesis and drawing reasonable interpretations of results from an individual article. Ultimately, it affects the generation of novel review findings. For example, one of the articles about women’s healthcare-seeking behaviours in developing countries reported a theme ‘social-cultural determinants of health as precursors of delays’. Instead of using this theme as one of the review findings, the reviewers should read and interpret beyond the given description in an article, compare and contrast themes, findings from one article with findings and themes from another article to find similarities and differences and to understand and explain bigger picture for their readers. Therefore, while developing literature summary tables, think twice before using the predeveloped themes. Including your themes in the summary tables (see figure 1 ) demonstrates to the readers that a robust method of data extraction and synthesis has been followed.

Tip 5: create your personalised template for literature summaries

Often templates are available for data extraction and development of literature summary tables. The available templates may be in the form of a table, chart or a structured framework that extracts some essential information about every article. The commonly used information may include authors, purpose, methods, key results and quality scores. While extracting all relevant information is important, such templates should be tailored to meet the needs of the individuals’ review. For example, for a review about the effectiveness of healthcare interventions, a literature summary table must include information about the intervention, its type, content timing, duration, setting, effectiveness, negative consequences, and receivers and implementers’ experiences of its usage. Similarly, literature summary tables for articles included in a meta-synthesis must include information about the participants’ characteristics, research context and conceptual contribution of each reviewed article so as to help the reader make an informed decision about the usefulness or lack of usefulness of the individual article in the review and the whole review.

In conclusion, narrative or systematic reviews are almost always conducted as a part of any educational project (thesis or dissertation) or academic or clinical research. Literature reviews are the foundation of research on a given topic. Robust and high-quality reviews play an instrumental role in guiding research, practice and policymaking. However, the quality of reviews is also contingent on rigorous data extraction and synthesis, which require developing literature summaries. We have outlined five tips that could enhance the quality of the data extraction and synthesis process by developing useful literature summaries.

  • Aromataris E ,
  • Rasheed SP ,

Twitter @Ahtisham04, @parveenazamali

Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

Competing interests None declared.

Patient consent for publication Not required.

Provenance and peer review Not commissioned; externally peer reviewed.

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Islam S, Frey N. Psychotherapy for the Treatment of Acute Musculoskeletal Pain: A Review of Clinical Effectiveness and Guidelines [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2020 Apr 17.

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Table 5 strengths and limitations of systematic reviews and meta-analyses amstar 10.

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CBT = Cognitive-behavioral techniques; GRADE = Grading of Recommendations, Assessment, Development and Evaluation; PRISMA = Preferred Reporting Items for Systematic Reviews and Meta-Analyses; RCT = randomized controlled trial

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  • Cite this Page Islam S, Frey N. Psychotherapy for the Treatment of Acute Musculoskeletal Pain: A Review of Clinical Effectiveness and Guidelines [Internet]. Ottawa (ON): Canadian Agency for Drugs and Technologies in Health; 2020 Apr 17. Table 5, Strengths and Limitations of Systematic Reviews and Meta-Analyses AMSTAR.
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  • StressModEx--Physiotherapist-led Stress Inoculation Training integrated with exercise for acute whiplash injury: study protocol for a randomised controlled trial. [J Physiother. 2015] StressModEx--Physiotherapist-led Stress Inoculation Training integrated with exercise for acute whiplash injury: study protocol for a randomised controlled trial. Ritchie C, Kenardy J, Smeets R, Sterling M. J Physiother. 2015 Jul; 61(3):157. Epub 2015 Jun 17.
  • Effect of Mindfulness-Based Stress Reduction vs Cognitive Behavioral Therapy or Usual Care on Back Pain and Functional Limitations in Adults With Chronic Low Back Pain: A Randomized Clinical Trial. [JAMA. 2016] Effect of Mindfulness-Based Stress Reduction vs Cognitive Behavioral Therapy or Usual Care on Back Pain and Functional Limitations in Adults With Chronic Low Back Pain: A Randomized Clinical Trial. Cherkin DC, Sherman KJ, Balderson BH, Cook AJ, Anderson ML, Hawkes RJ, Hansen KE, Turner JA. JAMA. 2016 Mar 22-29; 315(12):1240-9.
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  1. 21 Research Limitations Examples (2023)

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  1. Approaches , Analysis And Sources Of Literature Review ( RESEARCH METHODOLOGY AND IPR)

  2. Literature Review Part 2 (Type of Solution to avoid this issue) EDU2213

  3. Literature Review: Find Research gap and limitation in an article!

  4. Approaches to Literature Review

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COMMENTS

  1. 8 common problems with literature reviews and how to fix them

    In our recent paper in Nature Ecology and Evolution, we highlight 8 common problems with traditional literature review methods, provide examples for each from the field of environmental management and ecology, and provide practical solutions for ways to mitigate them. Problem. Solution. Lack of relevance - limited stakeholder engagement can ...

  2. Eight problems with literature reviews and how to fix them

    Environment. Policy*. Research Design. Systematic Reviews as Topic*. Traditional approaches to reviewing literature may be susceptible to bias and result in incorrect decisions. This is of particular concern when reviews address policy- and practice-relevant questions. Systematic reviews have been introduced as a more rigorous approach to ...

  3. Eight problems with literature reviews and how to fix them

    Gillian Petrok ofsky, Andrew S. Pullin9, Sini Savilaakso 10,11 and Gavin B. Stewart 12. T raditional approaches to reviewing literature may be susceptible to bias and result in incorrect decisions ...

  4. Eight common problems with science literature reviews and how to fix them

    The good news is that the limitations of traditional literature review approaches could be improved relatively easily with a few key procedures. Some of these are not prohibitively costly in terms ...

  5. How to Write a Literature Review

    Examples of literature reviews. Step 1 - Search for relevant literature. Step 2 - Evaluate and select sources. Step 3 - Identify themes, debates, and gaps. Step 4 - Outline your literature review's structure. Step 5 - Write your literature review.

  6. Systematic reviews: Brief overview of methods, limitations, and

    CONCLUSION. Siddaway 16 noted that, "The best reviews synthesize studies to draw broad theoretical conclusions about what the literature means, linking theory to evidence and evidence to theory" (p. 747). To that end, high quality systematic reviews are explicit, rigorous, and reproducible. It is these three criteria that should guide authors seeking to write a systematic review or editors ...

  7. Literature review as a research methodology: An ...

    A literature review can broadly be described as a more or less systematic way of collecting and synthesizing previous research (Baumeister & Leary, 1997; Tranfield, Denyer, & Smart, 2003). ... the limitations of the search method, and the quality of the search process, and they often lack details on how the analysis was conducted. Second, in ...

  8. What is a literature review?

    A literature or narrative review is a comprehensive review and analysis of the published literature on a specific topic or research question. The literature that is reviewed contains: books, articles, academic articles, conference proceedings, association papers, and dissertations. It contains the most pertinent studies and points to important ...

  9. Eight problems with literature reviews and how to fix them

    The authors also excluded/ignored grey literature (see point 5, below). In a review of tropical forest management impacts 32 and in a review of forest conservation policies 33, searches for ...

  10. Writing a literature review

    A formal literature review is an evidence-based, in-depth analysis of a subject. There are many reasons for writing one and these will influence the length and style of your review, but in essence a literature review is a critical appraisal of the current collective knowledge on a subject. Rather than just being an exhaustive list of all that ...

  11. Guidance on Conducting a Systematic Literature Review

    Literature review is an essential feature of academic research. Fundamentally, knowledge advancement must be built on prior existing work. To push the knowledge frontier, we must know where the frontier is. By reviewing relevant literature, we understand the breadth and depth of the existing body of work and identify gaps to explore.

  12. Limitations of the Study

    The limitations of the study are those characteristics of design or methodology that impacted or influenced the interpretation of the findings from your research. ... Lack of prior research studies on the topic-- citing prior research studies forms the basis of your literature review and helps lay a foundation for understanding the research ...

  13. Ten Simple Rules for Writing a Literature Review

    Literature reviews are in great demand in most scientific fields. Their need stems from the ever-increasing output of scientific publications .For example, compared to 1991, in 2008 three, eight, and forty times more papers were indexed in Web of Science on malaria, obesity, and biodiversity, respectively .Given such mountains of papers, scientists cannot be expected to examine in detail every ...

  14. Advantages and disadvantages of literature review

    According to the University of Illinois (2022), literature reviews allow researchers to gain familiarity with the existing knowledge in their selected field, as well as the boundaries and limitations of that field. Creation of new body of knowledge. One of the key advantages of literature review is that it creates new body of knowledge.

  15. Systematic reviews: Brief overview of methods, limitations, and resources

    REVIEW State of Reviews Systematic reviews: Brief overview of methods, limitations, and resources Jacqueline K. Owens Correspondence Jacqueline K. Owens. Email: [email protected] INTRODUCTION Systematic reviews are a valuable resource for nurses in academia and practice.1‐3 Well done systematic reviews, which include but

  16. Writing a Literature Review

    Writing a Literature Review. A literature review is a document or section of a document that collects key sources on a topic and discusses those sources in conversation with each other (also called synthesis ). The lit review is an important genre in many disciplines, not just literature (i.e., the study of works of literature such as novels ...

  17. Systematic and other reviews: criteria and complexities

    A systematic review follows explicit methodology to answer a well-defined research question by searching the literature comprehensively, evaluating the quantity and quality of research evidence rigorously, and analyzing the evidence to synthesize an answer to the research question. The evidence gathered in systematic reviews can be qualitative ...

  18. Approaching literature review for academic purposes: The Literature

    A sophisticated literature review (LR) can result in a robust dissertation/thesis by scrutinizing the main problem examined by the academic study; anticipating research hypotheses, methods and results; and maintaining the interest of the audience in how the dissertation/thesis will provide solutions for the current gaps in a particular field.

  19. Libraries: Writing a Literature Review: Phase 1: Scope of Review

    In specifying precisely one's research topic, one is also specifying appropriate limitations on the research. Limiting, for example, by time, personnel, gender, age, location, nationality, etc. results in a more focused and meaningful topic. Scope of the Literature Review. It is also important to determine the precise scope of the literature ...

  20. Limitations of the literature

    This work typically appears in a separate chapter in the thesis or dissertation under the title Literature Review. To help you, here are 10 typical examples often used to identify limitations in a particular body of literature—with a caveat—using education examples. 1. The sample size is too small and therefore not representative of the ...

  21. Five tips for developing useful literature summary tables for writing

    Literature reviews offer a critical synthesis of empirical and theoretical literature to assess the strength of evidence, develop guidelines for practice and policymaking, and identify areas for future research.1 It is often essential and usually the first task in any research endeavour, particularly in masters or doctoral level education. For effective data extraction and rigorous synthesis ...

  22. Narrative Reviews: Flexible, Rigorous, and Practical

    Narrative reviews have many strengths. They are flexible and practical, and ideally provide a readable, relevant synthesis of a diverse literature. Narrative reviews are often helpful for teaching or learning about a topic because they deliver a general overview. They are also useful for setting the stage for future research, as they offer an ...

  23. Full article: Engineering education 5.0: a systematic literature review

    The study conducted a review of the scientific literature from 2018 to 2023, the date of data extraction from the Scopus scientific database. A limitation of this research is that during the period of the screening, selection and analysis, and development of the framework, further research on competence-based engineering education may have been ...

  24. Demystifying the impact of educational leadership on teachers

    Another limitation of WoS is the underrepresentation of non-English language publications, ... 24 were quantitative, three were qualitative, and 1 was a literature review. Three of the quantitative studies used a longitudinal approach. Data collection involved both educational leaders and teachers in only five studies, while the remaining ...

  25. Behavior-analytic assessment and treatment of problem behavior

    Our review found 18 studies providing demonstrations of assessment and 11 studies providing demonstrations of treatment for the social escape function. Although there have been demonstrations of effective treatment for problem behavior maintained by social escape, the extant literature on treatment has been limited with respect to the number of ...

  26. The Literature Review: A Foundation for High-Quality Medical Education

    Purpose and Importance of the Literature Review. An understanding of the current literature is critical for all phases of a research study. Lingard 9 recently invoked the "journal-as-conversation" metaphor as a way of understanding how one's research fits into the larger medical education conversation. As she described it: "Imagine yourself joining a conversation at a social event.

  27. Applied Sciences

    Aseptic loosening is the most common failure mode for total hip arthroplasty, and the design of the implant plays a significant role in influencing the longevity and stability of the implant. Finite Element (FE) models have been demonstrated to be powerful numerical tools that allow for generating information supporting the device's safety and/or efficacy during pre-clinical assessment.

  28. Table 5, Strengths and Limitations of Systematic Reviews and Meta

    A systematic and comprehensive literature search was conducted, with predefined search strategy and no language restrictions applied and in multiple databases. In addition, a manual search from reference list of retrieved papers and review articles was also performed. The reporting of the search strategy followed the requirements of PRISMA ...