how to critique a literature review example

Literature reviews

• Introduction
• Conducting your search
• Store and organise the literature

Evaluate the information you have found

Critique the literature.

• Different subject areas
• Find literature reviews

When conducting your searches you may find many references that will not be suitable to use in your literature review.

• Skim through the resource - a quick read through the table of contents, the introductory paragraph or the abstract should indicate whether you need to read further or whether you can immediately discard the result.
• Evaluate the quality and reliability of the references you find - our page on evaluating information outlines what you need to consider when evaluating the books, journal articles, news and websites you find to ensure they are suitable for use in your literature review.

Critiquing the literature involves looking at the strength and weaknesses of the paper and evaluating the statements made by the author/s.

Books and resources on reading critically

• CASP Checklists Critical appraisal tools designed to be used when reading research. Includes tools for Qualitative studies, Systematic Reviews, Randomised Controlled Trials, Cohort Studies, Case Control Studies, Economic Evaluations, Diagnostic Studies and Clinical Prediction Rule.
• How to read critically - business and management From Postgraduate research in business - the aim of this chapter is to show you how to become a critical reader of typical academic literature in business and management.
• Learning to read critically in language and literacy Aims to develop skills of critical analysis and research design. It presents a series of examples of `best practice' in language and literacy education research.
• Critical appraisal in health sciences See tools for critically appraising health science research.

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• Last Updated: Dec 15, 2023 12:09 PM
• URL: https://guides.library.uq.edu.au/research-techniques/literature-reviews

Literature Reviews

• Introduction
• Tutorials and resources
• Step 1: Literature search
• Step 2: Analysis, synthesis, critique
• Step 3: Writing the review

If you need any assistance, please contact the library staff at the Georgia Tech Library Help website . 

Analysis, synthesis, critique

Literature reviews build a story. You are telling the story about what you are researching. Therefore, a literature review is a handy way to show that you know what you are talking about. To do this, here are a few important skills you will need.

Skill #1: Analysis

Analysis means that you have carefully read a wide range of the literature on your topic and have understood the main themes, and identified how the literature relates to your own topic. Carefully read and analyze the articles you find in your search, and take notes. Notice the main point of the article, the methodologies used, what conclusions are reached, and what the main themes are. Most bibliographic management tools have capability to keep notes on each article you find, tag them with keywords, and organize into groups.

Skill #2: Synthesis

After you’ve read the literature, you will start to see some themes and categories emerge, some research trends to emerge, to see where scholars agree or disagree, and how works in your chosen field or discipline are related. One way to keep track of this is by using a Synthesis Matrix .

Skill #3: Critique

As you are writing your literature review, you will want to apply a critical eye to the literature you have evaluated and synthesized. Consider the strong arguments you will make contrasted with the potential gaps in previous research. The words that you choose to report your critiques of the literature will be non-neutral. For instance, using a word like “attempted” suggests that a researcher tried something but was not successful. For example: 

There were some attempts by Smith (2012) and Jones (2013) to integrate a new methodology in this process.

On the other hand, using a word like “proved” or a phrase like “produced results” evokes a more positive argument. For example:

The new methodologies employed by Blake (2014) produced results that provided further evidence of X.

In your critique, you can point out where you believe there is room for more coverage in a topic, or further exploration in in a sub-topic.

Need more help?

If you are looking for more detailed guidance about writing your dissertation, please contact the folks in the Georgia Tech Communication Center .

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Article Summaries, Reviews & Critiques

• Writing an article SUMMARY
• Writing an article REVIEW

Writing an article CRITIQUE

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A critique asks you to evaluate an article and the author’s argument. You will need to look critically at what the author is claiming, evaluate the research methods, and look for possible problems with, or applications of, the researcher’s claims.

Introduction

Give an overview of the author’s main points and how the author supports those points. Explain what the author found and describe the process they used to arrive at this conclusion.

Body Paragraphs

Interpret the information from the article:

• Does the author review previous studies? Is current and relevant research used?
• What type of research was used – empirical studies, anecdotal material, or personal observations?
• Was the sample too small to generalize from?
• Was the participant group lacking in diversity (race, gender, age, education, socioeconomic status, etc.)
• For instance, volunteers gathered at a health food store might have different attitudes about nutrition than the population at large.
• How useful does this work seem to you? How does the author suggest the findings could be applied and how do you believe they could be applied?
• How could the study have been improved in your opinion?
• Does the author appear to have any biases (related to gender, race, class, or politics)?
• Is the writing clear and easy to follow? Does the author’s tone add to or detract from the article?
• How useful are the visuals (such as tables, charts, maps, photographs) included, if any? How do they help to illustrate the argument? Are they confusing or hard to read?
• What further research might be conducted on this subject?

Try to synthesize the pieces of your critique to emphasize your own main points about the author’s work, relating the researcher’s work to your own knowledge or to topics being discussed in your course.

From the Center for Academic Excellence (opens in a new window), University of Saint Joseph Connecticut

Additional Resources

All links open in a new window.

Writing an Article Critique (from The University of Arizona Global Campus Writing Center)

How to Critique an Article (from Essaypro.com)

How to Write an Article Critique (from EliteEditing.com.au)

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• CAREER FEATURE
• 04 December 2020
• Correction 09 December 2020

How to write a superb literature review

Andy Tay is a freelance writer based in Singapore.

You can also search for this author in PubMed   Google Scholar

Literature reviews are important resources for scientists. They provide historical context for a field while offering opinions on its future trajectory. Creating them can provide inspiration for one’s own research, as well as some practice in writing. But few scientists are trained in how to write a review — or in what constitutes an excellent one. Even picking the appropriate software to use can be an involved decision (see ‘Tools and techniques’). So Nature asked editors and working scientists with well-cited reviews for their tips.

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doi: https://doi.org/10.1038/d41586-020-03422-x

Interviews have been edited for length and clarity.

Updates & Corrections

Correction 09 December 2020 : An earlier version of the tables in this article included some incorrect details about the programs Zotero, Endnote and Manubot. These have now been corrected.

Hsing, I.-M., Xu, Y. & Zhao, W. Electroanalysis 19 , 755–768 (2007).

Article   Google Scholar  

Ledesma, H. A. et al. Nature Nanotechnol. 14 , 645–657 (2019).

Article   PubMed   Google Scholar  

Brahlek, M., Koirala, N., Bansal, N. & Oh, S. Solid State Commun. 215–216 , 54–62 (2015).

Choi, Y. & Lee, S. Y. Nature Rev. Chem . https://doi.org/10.1038/s41570-020-00221-w (2020).

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How to Write Critical Reviews

When you are asked to write a critical review of a book or article, you will need to identify, summarize, and evaluate the ideas and information the author has presented. In other words, you will be examining another person’s thoughts on a topic from your point of view.

Your stand must go beyond your “gut reaction” to the work and be based on your knowledge (readings, lecture, experience) of the topic as well as on factors such as criteria stated in your assignment or discussed by you and your instructor.

Make your stand clear at the beginning of your review, in your evaluations of specific parts, and in your concluding commentary.

Remember that your goal should be to make a few key points about the book or article, not to discuss everything the author writes.

Understanding the Assignment

To write a good critical review, you will have to engage in the mental processes of analyzing (taking apart) the work–deciding what its major components are and determining how these parts (i.e., paragraphs, sections, or chapters) contribute to the work as a whole.

Analyzing the work will help you focus on how and why the author makes certain points and prevent you from merely summarizing what the author says. Assuming the role of an analytical reader will also help you to determine whether or not the author fulfills the stated purpose of the book or article and enhances your understanding or knowledge of a particular topic.

Be sure to read your assignment thoroughly before you read the article or book. Your instructor may have included specific guidelines for you to follow. Keeping these guidelines in mind as you read the article or book can really help you write your paper!

Also, note where the work connects with what you’ve studied in the course. You can make the most efficient use of your reading and notetaking time if you are an active reader; that is, keep relevant questions in mind and jot down page numbers as well as your responses to ideas that appear to be significant as you read.

Please note: The length of your introduction and overview, the number of points you choose to review, and the length of your conclusion should be proportionate to the page limit stated in your assignment and should reflect the complexity of the material being reviewed as well as the expectations of your reader.

Write the introduction

Below are a few guidelines to help you write the introduction to your critical review.

Introduce your review appropriately

Begin your review with an introduction appropriate to your assignment.

If your assignment asks you to review only one book and not to use outside sources, your introduction will focus on identifying the author, the title, the main topic or issue presented in the book, and the author’s purpose in writing the book.

If your assignment asks you to review the book as it relates to issues or themes discussed in the course, or to review two or more books on the same topic, your introduction must also encompass those expectations.

Explain relationships

For example, before you can review two books on a topic, you must explain to your reader in your introduction how they are related to one another.

Within this shared context (or under this “umbrella”) you can then review comparable aspects of both books, pointing out where the authors agree and differ.

In other words, the more complicated your assignment is, the more your introduction must accomplish.

Finally, the introduction to a book review is always the place for you to establish your position as the reviewer (your thesis about the author’s thesis).

As you write, consider the following questions:

• Is the book a memoir, a treatise, a collection of facts, an extended argument, etc.? Is the article a documentary, a write-up of primary research, a position paper, etc.?
• Who is the author? What does the preface or foreword tell you about the author’s purpose, background, and credentials? What is the author’s approach to the topic (as a journalist? a historian? a researcher?)?
• What is the main topic or problem addressed? How does the work relate to a discipline, to a profession, to a particular audience, or to other works on the topic?
• What is your critical evaluation of the work (your thesis)? Why have you taken that position? What criteria are you basing your position on?

Provide an overview

In your introduction, you will also want to provide an overview. An overview supplies your reader with certain general information not appropriate for including in the introduction but necessary to understanding the body of the review.

Generally, an overview describes your book’s division into chapters, sections, or points of discussion. An overview may also include background information about the topic, about your stand, or about the criteria you will use for evaluation.

The overview and the introduction work together to provide a comprehensive beginning for (a “springboard” into) your review.

• What are the author’s basic premises? What issues are raised, or what themes emerge? What situation (i.e., racism on college campuses) provides a basis for the author’s assertions?
• How informed is my reader? What background information is relevant to the entire book and should be placed here rather than in a body paragraph?

Write the body

The body is the center of your paper, where you draw out your main arguments. Below are some guidelines to help you write it.

Organize using a logical plan

Organize the body of your review according to a logical plan. Here are two options:

• First, summarize, in a series of paragraphs, those major points from the book that you plan to discuss; incorporating each major point into a topic sentence for a paragraph is an effective organizational strategy. Second, discuss and evaluate these points in a following group of paragraphs. (There are two dangers lurking in this pattern–you may allot too many paragraphs to summary and too few to evaluation, or you may re-summarize too many points from the book in your evaluation section.)
• Alternatively, you can summarize and evaluate the major points you have chosen from the book in a point-by-point schema. That means you will discuss and evaluate point one within the same paragraph (or in several if the point is significant and warrants extended discussion) before you summarize and evaluate point two, point three, etc., moving in a logical sequence from point to point to point. Here again, it is effective to use the topic sentence of each paragraph to identify the point from the book that you plan to summarize or evaluate.

Questions to keep in mind as you write

With either organizational pattern, consider the following questions:

• What are the author’s most important points? How do these relate to one another? (Make relationships clear by using transitions: “In contrast,” an equally strong argument,” “moreover,” “a final conclusion,” etc.).
• What types of evidence or information does the author present to support his or her points? Is this evidence convincing, controversial, factual, one-sided, etc.? (Consider the use of primary historical material, case studies, narratives, recent scientific findings, statistics.)
• Where does the author do a good job of conveying factual material as well as personal perspective? Where does the author fail to do so? If solutions to a problem are offered, are they believable, misguided, or promising?
• Which parts of the work (particular arguments, descriptions, chapters, etc.) are most effective and which parts are least effective? Why?
• Where (if at all) does the author convey personal prejudice, support illogical relationships, or present evidence out of its appropriate context?

Keep your opinions distinct and cite your sources

Remember, as you discuss the author’s major points, be sure to distinguish consistently between the author’s opinions and your own.

Keep the summary portions of your discussion concise, remembering that your task as a reviewer is to re-see the author’s work, not to re-tell it.

And, importantly, if you refer to ideas from other books and articles or from lecture and course materials, always document your sources, or else you might wander into the realm of plagiarism.

Include only that material which has relevance for your review and use direct quotations sparingly. The Writing Center has other handouts to help you paraphrase text and introduce quotations.

Write the conclusion

You will want to use the conclusion to state your overall critical evaluation.

You have already discussed the major points the author makes, examined how the author supports arguments, and evaluated the quality or effectiveness of specific aspects of the book or article.

Now you must make an evaluation of the work as a whole, determining such things as whether or not the author achieves the stated or implied purpose and if the work makes a significant contribution to an existing body of knowledge.

Consider the following questions:

• Is the work appropriately subjective or objective according to the author’s purpose?
• How well does the work maintain its stated or implied focus? Does the author present extraneous material? Does the author exclude or ignore relevant information?
• How well has the author achieved the overall purpose of the book or article? What contribution does the work make to an existing body of knowledge or to a specific group of readers? Can you justify the use of this work in a particular course?
• What is the most important final comment you wish to make about the book or article? Do you have any suggestions for the direction of future research in the area? What has reading this work done for you or demonstrated to you?

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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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How to Critique Literature

Last Updated: March 5, 2024 Approved

This article was co-authored by Michelle Golden, PhD . Michelle Golden is an English teacher in Athens, Georgia. She received her MA in Language Arts Teacher Education in 2008 and received her PhD in English from Georgia State University in 2015. wikiHow marks an article as reader-approved once it receives enough positive feedback. In this case, 88% of readers who voted found the article helpful, earning it our reader-approved status. This article has been viewed 244,848 times.

A literature critique, sometimes called a literary analysis or a literary critical analysis, is an examination of a piece of literature. The scope of a critique of literature may be to examine a single aspect of the work, or the work in its entirety, and involves breaking the literary piece apart into its separate components and evaluating how they fit together to accomplish the piece's purpose. Literary critiques are commonly executed by students, scholars, and literary critics, but anyone can learn how to critique literature!

Conducting a Basic Critique for Beginners

• For example, for a T-chart, list the names of the characters in one column and their actions in another as you read. After reading, you can add a column with why you think they did each action.

• This is similar to artwork. Instead of looking at a painting to figure out what the artist was communicating, just look at what is literally present in the painting. For example, what items are present in Van Gogh’s ‘’Starry Night’’? Don’t think about what he is trying to say in this painting; think about the stars, the swirling night sky, and the houses below.

• For example, ask yourself, why does the witch turn the prince into a beast in Beauty and the Beast? What does this action suggest about human nature?
• Also think about what lesson the reader can learn from the characters. What does the Beast teach us?

• The format for a thesis may look something like this: _______ is true because __________, ____________, and ___________. [3] X Research source The first blank is your opinion. For example, The Beast teaches us that we should be hospitable to everyone.
• The rest of the blanks tell why your opinion is true: The Beast teaches us that we should be hospitable to everyone because he learns from his mistake, becomes a compassionate person through his time as a beast, and regrets that he was ever rude to the witch.
• However, keep in mind that there are many different ways to form a thesis. What is most important if to make sure that your thesis includes a claim and a summary of the reasons for your claim. For example, you might phrase your thesis as “Because the Beast suffers for his actions, Beauty and the Beast argues that we should be hospitable to everyone and this theme carries through the story.”

• You can summarize these events, or use direct quotes from the book, but both need to have a page number. This prevents plagiarism.
• For example, you might use a quote that shows how the Beast is inhospitable as one of your first examples. Then, you might use other examples from the text to show the continuation of this theme.
• You do not have to use direct quotes all of the time. You can also paraphrase a passage by putting it into your own words, or summarize longer passages by describing the events in a less detailed way in your own words. No matter if you are quoting, paraphrasing, or summarizing, make sure that you include a page number for your evidence.

• Fill in the outline with topic sentences and events from the literature that support each topic sentence.

• Close the essay with a conclusion paragraph, where you summarize the essay in just a few sentences.

Applying Advanced Critical Techniques

• You should read with a pen and paper handy, as well as with a dictionary. Write down the main ideas in the margins and look up words as you go.
• Ask “how,” “why,” and “so what” questions to help you read critically.

• Evaluate elements of the work as you go, such as plot, themes, instances of character development, setting, symbols, conflicts, and point of view. [6] X Research source Think about how these elements interact to form the main theme.

• making a list,
• mapping out a web, and
• freewriting.
• For example, while reading Pride and Prejudice, you might feel that Mr. Darcy’s character needed more development than Jane Austen gave him, or you might prefer Jane’s character to Lizzy’s and feel that she would have made a better heroine (for example, Jane shares a name with the author, giving you grounds to explore the argument that Austen might have actually preferred her). Make a list, web, or freewrite out of ideas like these.

• The thesis should present your opinion in an arguable manner accompanied by a solid reason why your opinion is true.
• The formula for a basic thesis statement might look like this: _______ is true because of __________, ____________, and ___________. [8] X Research source

• You can also take advantage of an outline to form key sentences like the hook (first line of the intro paragraph), topic and transition sentences for each body paragraph, and your conclusion.

• Look at your notes and identify any patterns you see in the text that support your thesis statement, such as how no one is ever sure what Mr. Darcy is doing until after the fact, contributing to a lack of character development in Pride and Prejudice (if you were trying to prove the validity of an argument that Mr. Darcy is not developed enough, for example).
• You must include a page number or authorial attribution anytime that you: talk about a specific event; paraphrase a quote; paraphrase a passage; or use any direct quote. You usually insert a page number in parentheses after the sentence.

• You should also address any criticism that does not agree with your thesis, as refuting the counterargument also builds your credibility.

• If you created your outline on a word processor, then you can simply fill in the outline with additional information.
• You can also treat the outline as a roadmap. Consult it as you draft your paper to make sure that you are including all of the points and examples that you have identified.

• MLA is more common for literary-based essays, but you should ask your instructor if you are not sure.

• For example, after offering a quote, you might explain what the quote means or demonstrates as well as how it supports your thesis. Do not simply paraphrase or summarize the quotes after you offer them. Summary does not show critical thinking. Instead, try to explain the significance of each quote or example to your readers.
• Try to create quote sandwiches. A quote sandwich is simply how you position a quote in an essay. You should have a sentence introducing the quote and its author, then have the quote itself, followed by one or more sentences analyzing the quote right after it.
• Make sure you include a references/works cited list with all sources you quote from or paraphrase in the essay. This prevents plagiarism.

Evaluating Literature as You Read

• Questioning the title helps in determining the main theme and contributes to a more accurate critique.

• Setting—description of the surroundings.
• Plot—events of the text.
• Characters—the motivations and depth of each character, such as how much they change or don’t change as a result of the events. Characters can be people, objects, even ideas (especially in poetry).
• Conflict—the opposition that the main character encounters and its climax and resolution.
• Themes—what the narrator observes about human nature.
• Point of view—the way that a character thinks, whether it is curious, condescending, etc. Can also be the perspective the text is told, whether in first person, third person, etc.
• Tone—the way the text feels, whether sad, happy, angry, apathetic, etc.
• Symbols—objects, people, or places that repeat consistently throughout the story and seem to represent another abstract idea.

• You may want to write down your interpretation of the work at this point, as it is an excellent springboard into a thesis statement, if you end up needing to write a paper about this text.
• You can review outside sources such as peer reviewed articles and books to verify that your interpretation is accurate or needs work.

Community Q&A

• You should always consider how the writer's techniques contribute to the overall meaning of the text. Thanks Helpful 0 Not Helpful 0
• If you don't feel you have a good grasp of all the specific components after the first reading of a literary work, read it over again, with the components in mind, before you critique. Thanks Helpful 0 Not Helpful 0
• Be careful not to summarize the entire work when you critique literature. It is your job to evaluate the work's meaning, not to outline its plot. Thanks Helpful 0 Not Helpful 0

• Remember that the critical approaches mentioned above are complicated and take time to master. Unless you are already familiar with them or are completing an assignment using them, you may want to stay away from them for now. Thanks Helpful 1 Not Helpful 0

You Might Also Like

• ↑ http://www.scholastic.com/teachers/lesson-plan/graphic-organizers-reading-comprehension
• ↑ http://writingcenter.unc.edu/handouts/thesis-statements/
• ↑ https://owl.english.purdue.edu/owl/resource/545/01/
• ↑ https://www.winthrop.edu/uploadedFiles/cas/english/ReadingCritically.pdf
• ↑ http://faculty.weber.edu/vramirez/hnscompoflit.htm
• ↑ http://writingcenter.unc.edu/handouts/brainstorming/

About This Article

To critique literature, start by carefully reading the text and then coming up with an opinion, like whether or not you think the author did a good job getting their main point across. Then, find evidence in the text to support your opinion, including things like quotes, events in the story, and actions the characters made. Once you have your argument and evidence support it, write your critique so that each paragraph addresses a different piece of evidence. To learn how to evaluate literature as you're reading it so it's easier to critique, scroll down! Did this summary help you? Yes No

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YSN Doctoral Programs: Steps in Conducting a Literature Review

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What is a literature review?

A literature review is an integrated analysis -- not just a summary-- of scholarly writings and other relevant evidence related directly to your research question.  That is, it represents a synthesis of the evidence that provides background information on your topic and shows a association between the evidence and your research question.

A literature review may be a stand alone work or the introduction to a larger research paper, depending on the assignment.  Rely heavily on the guidelines your instructor has given you.

Why is it important?

A literature review is important because it:

• Explains the background of research on a topic.
• Demonstrates why a topic is significant to a subject area.
• Discovers relationships between research studies/ideas.
• Identifies major themes, concepts, and researchers on a topic.
• Identifies critical gaps and points of disagreement.
• Discusses further research questions that logically come out of the previous studies.

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1. Choose a topic. Define your research question.

Your literature review should be guided by your central research question.  The literature represents background and research developments related to a specific research question, interpreted and analyzed by you in a synthesized way.

• Make sure your research question is not too broad or too narrow.  Is it manageable?
• Begin writing down terms that are related to your question. These will be useful for searches later.
• If you have the opportunity, discuss your topic with your professor and your class mates.

2. Decide on the scope of your review

How many studies do you need to look at? How comprehensive should it be? How many years should it cover? 

• This may depend on your assignment.  How many sources does the assignment require?

3. Select the databases you will use to conduct your searches.

Make a list of the databases you will search. 

Where to find databases:

• use the tabs on this guide
• Find other databases in the Nursing Information Resources web page
• More on the Medical Library web page
• ... and more on the Yale University Library web page

4. Conduct your searches to find the evidence. Keep track of your searches.

• Use the key words in your question, as well as synonyms for those words, as terms in your search. Use the database tutorials for help.
• Save the searches in the databases. This saves time when you want to redo, or modify, the searches. It is also helpful to use as a guide is the searches are not finding any useful results.
• Review the abstracts of research studies carefully. This will save you time.
• Use the bibliographies and references of research studies you find to locate others.
• Check with your professor, or a subject expert in the field, if you are missing any key works in the field.
• Ask your librarian for help at any time.
• Use a citation manager, such as EndNote as the repository for your citations. See the EndNote tutorials for help.

Review the literature

Some questions to help you analyze the research:

• What was the research question of the study you are reviewing? What were the authors trying to discover?
• Was the research funded by a source that could influence the findings?
• What were the research methodologies? Analyze its literature review, the samples and variables used, the results, and the conclusions.
• Does the research seem to be complete? Could it have been conducted more soundly? What further questions does it raise?
• If there are conflicting studies, why do you think that is?
• How are the authors viewed in the field? Has this study been cited? If so, how has it been analyzed?

Tips: 

• Review the abstracts carefully.  
• Keep careful notes so that you may track your thought processes during the research process.
• Create a matrix of the studies for easy analysis, and synthesis, across all of the studies.
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• Volume 19, Issue 1
• Reviewing the literature
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• Joanna Smith 1 ,
• Helen Noble 2
• 1 School of Healthcare, University of Leeds , Leeds , UK
• 2 School of Nursing and Midwifery, Queens's University Belfast , Belfast , UK
• Correspondence to Dr Joanna Smith , School of Healthcare, University of Leeds, Leeds LS2 9JT, UK; j.e.smith1{at}leeds.ac.uk

https://doi.org/10.1136/eb-2015-102252

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If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Implementing evidence into practice requires nurses to identify, critically appraise and synthesise research. This may require a comprehensive literature review: this article aims to outline the approaches and stages required and provides a working example of a published review.

Are there different approaches to undertaking a literature review?

What stages are required to undertake a literature review.

The rationale for the review should be established; consider why the review is important and relevant to patient care/safety or service delivery. For example, Noble et al 's 4 review sought to understand and make recommendations for practice and research in relation to dialysis refusal and withdrawal in patients with end-stage renal disease, an area of care previously poorly described. If appropriate, highlight relevant policies and theoretical perspectives that might guide the review. Once the key issues related to the topic, including the challenges encountered in clinical practice, have been identified formulate a clear question, and/or develop an aim and specific objectives. The type of review undertaken is influenced by the purpose of the review and resources available. However, the stages or methods used to undertake a review are similar across approaches and include:

Formulating clear inclusion and exclusion criteria, for example, patient groups, ages, conditions/treatments, sources of evidence/research designs;

Justifying data bases and years searched, and whether strategies including hand searching of journals, conference proceedings and research not indexed in data bases (grey literature) will be undertaken;

Developing search terms, the PICU (P: patient, problem or population; I: intervention; C: comparison; O: outcome) framework is a useful guide when developing search terms;

Developing search skills (eg, understanding Boolean Operators, in particular the use of AND/OR) and knowledge of how data bases index topics (eg, MeSH headings). Working with a librarian experienced in undertaking health searches is invaluable when developing a search.

Once studies are selected, the quality of the research/evidence requires evaluation. Using a quality appraisal tool, such as the Critical Appraisal Skills Programme (CASP) tools, 5 results in a structured approach to assessing the rigour of studies being reviewed. 3 Approaches to data synthesis for quantitative studies may include a meta-analysis (statistical analysis of data from multiple studies of similar designs that have addressed the same question), or findings can be reported descriptively. 6 Methods applicable for synthesising qualitative studies include meta-ethnography (themes and concepts from different studies are explored and brought together using approaches similar to qualitative data analysis methods), narrative summary, thematic analysis and content analysis. 7 Table 1 outlines the stages undertaken for a published review that summarised research about parents’ experiences of living with a child with a long-term condition. 8

• View inline

An example of rapid evidence assessment review

In summary, the type of literature review depends on the review purpose. For the novice reviewer undertaking a review can be a daunting and complex process; by following the stages outlined and being systematic a robust review is achievable. The importance of literature reviews should not be underestimated—they help summarise and make sense of an increasingly vast body of research promoting best evidence-based practice.

• ↵ Centre for Reviews and Dissemination . Guidance for undertaking reviews in health care . 3rd edn . York : CRD, York University , 2009 .
• ↵ Canadian Best Practices Portal. http://cbpp-pcpe.phac-aspc.gc.ca/interventions/selected-systematic-review-sites / ( accessed 7.8.2015 ).
• Bridges J , et al
• ↵ Critical Appraisal Skills Programme (CASP). http://www.casp-uk.net / ( accessed 7.8.2015 ).
• Dixon-Woods M ,
• Shaw R , et al
• Agarwal S ,
• Jones D , et al
• Cheater F ,

Twitter Follow Joanna Smith at @josmith175

Competing interests None declared.

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Understanding and Evaluating Systematic Reviews and Meta-analyses

Michael bigby.

From the Department of Dermatology, Harvard Medical School, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA

A systematic review is a summary of existing evidence that answers a specific clinical question, contains a thorough, unbiased search of the relevant literature, explicit criteria for assessing studies and structured presentation of the results. A systematic review that incorporates quantitative pooling of similar studies to produce an overall summary of treatment effects is a meta-analysis. A systematic review should have clear, focused clinical objectives containing four elements expressed through the acronym PICO (Patient, group of patients, or problem, an Intervention, a Comparison intervention and specific Outcomes). Explicit and thorough search of the literature is a pre-requisite of any good systematic review. Reviews should have pre-defined explicit criteria for what studies would be included and the analysis should include only those studies that fit the inclusion criteria. The quality (risk of bias) of the primary studies should be critically appraised. Particularly the role of publication and language bias should be acknowledged and addressed by the review, whenever possible. Structured reporting of the results with quantitative pooling of the data must be attempted, whenever appropriate. The review should include interpretation of the data, including implications for clinical practice and further research. Overall, the current quality of reporting of systematic reviews remains highly variable.

Introduction

A systematic review is a summary of existing evidence that answers a specific clinical question, contains a thorough, unbiased search of the relevant literature, explicit criteria for assessing studies and structured presentation of the results. A systematic review can be distinguished from a narrative review because it will have explicitly stated objectives (the focused clinical question), materials (the relevant medical literature) and methods (the way in which studies are assessed and summarized).[ 1 , 2 ] A systematic review that incorporates quantitative pooling of similar studies to produce an overall summary of treatment effects is a meta-analysis.[ 1 , 2 ] Meta-analysis may allow recognition of important treatment effects by combining the results of small trials that individually might lack the power to consistently demonstrate differences among treatments.[ 1 ]

With over 200 speciality dermatology journals being published, the amount of data published just in the dermatologic literature exceeds our ability to read it.[ 3 ] Therefore, keeping up with the literature by reading journals is an impossible task. Systematic reviews provide a solution to handle information overload for practicing physicians.

Criteria for reporting systematic reviews have been developed by a consensus panel first published as Quality of Reporting of Meta-analyses (QUOROM) and later refined as Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA).[ 4 , 5 ] This detailed, 27-item checklist contains items that should be included and reported in high quality systematic reviews and meta-analyses. The methods for understanding and appraising systematic reviews and meta-analyses presented in this paper are a subset of the PRISMA criteria.

The items that are the essential features of a systematic review include having clear objectives, explicit criteria for study selection, an assessment of the quality of included studies, criteria for which studies can be combined, appropriate analysis and presentation of results and practical conclusions that are based on the evidence evaluated [ Table 1 ]. Meta-analysis is only appropriate if the included studies are conceptually similar. Meta-analyses should only be conducted after a systematic review.[ 1 , 6 ]

Criteria for evaluating a systematic review or the meta-analysis

A Systematic Review Should Have Clear, Focused Clinical Objectives

A focused clinical question for a systematic review should contain the same four elements used to formulate well-built clinical questions for individual studies, namely a Patient, group of patients, or problem, an Intervention, a Comparison intervention and specific Outcomes.[ 7 ] These features can be remembered by the acronym PICO. The interventions and comparison interventions should be adequately described so that what was done can be reproduced in future studies and in practice. For diseases with established effective treatments, comparisons of new treatments or regimens to established treatments provide the most useful information. The outcomes reported should be those that are most relevant to physicians and patients.[ 1 ]

Explicit and Thorough Search of the Literature

A key question to ask of a systematic review is: “Is it unlikely that important, relevant studies were missed?” A sound systematic review can be performed only if most or all of the available data are examined. An explicit and thorough search of the literature should be performed. It should include searching several electronic bibliographic databases including the Cochrane Controlled Trials Registry, which is part of the Cochrane Library, Medline, Embase and Literatura Latino Americana em Ciências da Saúde. Bibliographies of retrieved studies, review articles and textbooks should be examined for studies fitting inclusion criteria. There should be no language restrictions. Additional sources of data include scrutiny of citation lists in retrieved articles, hand-searching for conference reports, prospective trial registers (e.g., clinical trials.gov for the USA and clinical trialsregister.eu for the European union) and contacting key researchers, authors and drug companies.[ 1 , 8 ]

Reviews should have Pre-defined Explicit Criteria for what Studies would be Included and the Analysis should Include Only those Studies that Fit the Inclusion Criteria

The overwhelming majority of systematic reviews involve therapy. Randomized, controlled clinical trials should therefore be used for systematic reviews of therapy if they are available, because they are generally less susceptible to selection and information bias in comparison with other study designs.[ 1 , 9 ]

Systematic reviews of diagnostic studies and harmful effects of interventions are increasingly being performed and published. Ideally, diagnostic studies included in systematic reviews should be cohort studies of representative populations. The studies should include a criterion (gold) standard test used to establish a diagnosis that is applied uniformly and blinded to the results of the test(s) being studied.[ 1 , 9 ]

Randomized controlled trials can be included in systematic reviews of studies of adverse effects of interventions if the events are common. For rare adverse effects, case-control studies, post-marketing surveillance studies and case reports are more appropriate.[ 1 , 9 ]

The Quality (Risk of Bias) of the Primary Studies should be Critically Appraised

The risk of bias of included therapeutic trials is assessed using the criteria that are used to evaluate individual randomized controlled clinical trials. The quality criteria commonly used include concealed, random allocation; groups similar in terms of known prognostic factors; equal treatment of groups; blinding of patients, researchers and analyzers of the data to treatment allocation and accounting for all patients entered into the trial when analyzing the results (intention-to-treat design).[ 1 ] Absence of these items has been demonstrated to increase the risk of bias of systematic reviews and to exaggerate the treatment effects in individual studies.[ 10 ]

Structured Reporting of the Results with Quantitative Pooling of the Data, if Appropriate

Systematic reviews that contain studies that have results that are similar in magnitude and direction provide results that are most likely to be true and useful. It may be impossible to draw firm conclusions from systematic reviews in which studies have results of widely different magnitude and direction.[ 1 , 9 ]

Meta-analysis should only be performed to synthesize results from different trials if the trials have conceptual homogeneity.[ 1 , 6 , 9 ] The trials must involve similar patient populations, have used similar treatments and have measured results in a similar fashion at a similar point in time.

Once conceptual homogeneity is established and the decision to combine results is made, there are two main statistical methods by which results are combined: random-effects models (e.g., DerSimonian and Laird) and fixed-effects models (e.g., Peto or Mantel-Haenszel).[ 11 ] Random-effects models assume that the results of the different studies may come from different populations with varying responses to treatment. Fixed-effects models assume that each trial represents a random sample of a single population with a single response to treatment [ Figure 1 ]. In general, random-effects models are more conservative (i.e., random-effects models are less likely to show statistically significant results than fixed-effects models). When the combined studies have statistical homogeneity (i.e., when the studies are reasonably similar in direction, magnitude and variability), random-effects and fixed-effects models give similar results.

Fixed-effects models (a) assume that each trial represents a random sample (colored curves) of a single population with a single response to treatment. Random-effects models (b) assume that the different trials’ results (colored curves) may come from different populations with varying responses to treatment.

The point estimates and confidence intervals of the individual trials and the synthesis of all trials in meta-analysis are typically displayed graphically in a forest plot [ Figure 2 ].[ 12 ] Results are most commonly expressed as the odds ratio (OR) of the treatment effect (i.e., the odds of achieving a good outcome in the treated group divided by the odds of achieving a good result in the control group) but can be expressed as risk differences (i.e., difference in response rate) or relative risk (probability of achieving a good outcome in the treated group divided by the probability in the control group). An OR of 1 (null) indicates no difference between treatment and control and is usually represented by a vertical line passing through 1 on the x-axis. An OR of greater or less than 1 implies that the treatment is superior or inferior to the control respectively.

Annotated results of a meta-analysis of six studies, using random effects models reported as odd ratios using MIX version 1.7 (Bax L, Yu LM, Ikeda N, Tsuruta H, Moons KGM. Development and validation of MIX: comprehensive free software for meta-analysis of causal research data. BMC Med Res Methodol http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1626481/ ). The central graph is a typical Forest Plot

The point estimate of individual trials is indicated by a square whose size is proportional to the size of the trial (i.e., number of patients analyzed). The precision of the trial is represented by the 95% confidence interval that appears in Forest Plots as the brackets surrounding point estimate. If the 95% confidence interval (brackets) does not cross null (OR of 1), then the individual trial is statistically significant at the P = 0.05 level.[ 12 ] The summary value for all trials is shown graphically as a parallelogram whose size is proportional to the total number of patients analyzed from all trials. The lateral tips of the parallelogram represent the 95% confidence interval and if they do not cross null (OR of 1), then the summary value of the meta-analysis is statistically significant at the P = 0.05 level. ORs can be converted to risk differences and numbers needed to treat (NNTs) if the event rate in the control group is known [ Table 2 ].[ 13 , 14 ]

Deriving numbers needed to treat from a treatment's odds ratio and the observed or expected event rates of untreated groups or individuals

The difference in response rate and its reciprocal, the NNT, are the most easily understood measures of the magnitude of the treatment effect.[ 1 , 9 ] The NNT represents the number of patients one would need to treat in order to achieve one additional cure. Whereas the interpretation of NNT might be straightforward within one trial, interpretation of NNT requires some caution within a systematic review, as this statistic is highly sensitive to baseline event rates.[ 1 ]

For example, if a treatment A is 30% more effective than treatment B for clearing psoriasis and 50% of people on treatment B are cleared with therapy, then 65% will clear with treatment A. These results correspond to a rate difference of 15% (65-50) and an NNT of 7 (1/0.15). This difference sounds quite worthwhile clinically. However if the baseline clearance rate for treatment B in another trial or setting is only 30%, the rate difference will be only 9% and the NNT now becomes 11 and if the baseline clearance rate is 10%, then the NNT for treatment A will be 33, which is perhaps less worthwhile.[ 1 ]

Therefore, NNT summary measures within a systematic review should be interpreted with caution because “control” or baseline event rates usually differ considerably between studies.[ 1 , 15 ] Instead, a range of NNTs for a range of plausible control event rates that occur in different clinical settings should be given, along with their 95% confidence intervals.[ 1 , 16 ]

The data used in a meta-analysis can be tested for statistical heterogeneity. Methods to tests for statistical heterogeneity include the χ 2 and I.[ 2 , 11 , 17 ] Tests for statistical heterogeneity are typically of low power and hence detecting statistical homogeneity does not mean clinical homogeneity. When there is evidence of heterogeneity, reasons for heterogeneity between studies – such as different disease subgroups, intervention dosage, or study quality – should be sought.[ 11 , 17 ] Detecting the source of heterogeneity generally requires sub-group analysis, which is only possible when data from many or large trials are available.[ 1 , 9 ]

In some systematic reviews in which a large number of trials have been performed, it is possible to evaluate whether certain subgroups (e.g. children versus adults) are more likely to benefit than others. Subgroup analysis is rarely possible in dermatology, because few trials are available. Subgroup analyses should always be pre-specified in a systematic review protocol in order to avoid spurious post hoc claims.[ 1 , 9 ]

The Importance of Publication Bias

Publication bias is the tendency that studies that show positive effects are more likely to be published and are easier to find.[ 1 , 18 ] It results from allowing factors other than the quality of the study to influence its acceptability for publication. Factors such as the sample size, the direction and statistical significance of findings, or the investigators’ perception of whether the findings are “interesting,” are related to the likelihood of publication.[ 1 , 19 , 20 ] Negative studies with small sample size are less likely to be published.[ 1 , 19 , 20 ] Studies published are often dominated by the pharmaceutical company sponsored trials of new, expensive treatments often compared with the placebo.

For many diseases, the studies published are dominated by drug company-sponsored trials of new, expensive treatments. Such studies are almost always “positive.”[ 1 , 21 , 22 ] This bias in publication can result in data-driven systematic reviews that draw more attention to those medicines. Systematic reviews that have been sponsored directly or indirectly by industry are also prone to bias through over-inclusion of unpublished “positive” studies that are kept “on file” by that company and by not including or not finishing registered trials whose results are negative.[ 1 , 23 ] The creation of study registers (e.g. http://clinicaltrials.gov ) and advance publication of research designs have been proposed as ways to prevent publication bias.[ 1 , 24 , 25 ] Many dermatology journals now require all their published trials to have been registered beforehand, but this policy is not well policed.[ 1 ]

Language bias is the tendency for studies that are “positive” to be published in an English-language journal and be more quickly found than inconclusive or negative studies.[ 1 , 26 ] A thorough systematic review should therefore not restrict itself to journals published in English.[ 1 ]

Publication bias can be detected by using a simple graphic test (funnel plot), by calculating the fail-safe N, Begg's rank correlation method, Egger regression method and others.[ 1 , 9 , 11 , 27 , 28 ] These techniques are of limited value when less than 10 randomized controlled trials are included. Testing for publication bias is often not possible in systematic reviews of skin diseases, due to the limited number and sizes of trials.[ 1 , 9 ]

Question-driven systematic reviews answer the clinical questions of most concern to practitioners. In many cases, studies that are of most relevance to doctors and patients have not been done in the field of dermatology, due to inadequate sources of independent funding.[ 1 , 9 ]

The Quality of Reporting of Systematic Reviews

The quality of reporting of systematic reviews is highly variable.[ 1 ] One cross-sectional study of 300 systematic reviews published in Medline showed that over 90% were reported in specialty journals. Funding sources were not reported in 40% of reviews. Only two-thirds reported the range of years that the literature was searched for trials. Around a third of reviews failed to provide a quality assessment of the included studies and only half of the reviews included the term “systematic review” or “meta-analysis” in the title.[ 1 , 29 ]

The Review should Include Interpretation of the Data, Including Implications for Clinical Practice and Further Research

The conclusions in the discussion section of a systematic review should closely reflect the data that have been presented within that review. Clinical recommendations can be made when conclusive evidence is found, analyzed and presented. The authors should make it clear which of the treatment recommendations are based on the review data and which reflect their own judgments.[ 1 , 9 ]

Many reviews in dermatology, however, find little evidence to address the questions posed. The review may still be of value even if it lacks conclusive evidence, especially if the question addressed is an important one.[ 1 , 30 ] For example, the systematic review may provide the authors with the opportunity to call for primary research in an area and to make recommendations on study design and outcomes that might help future researchers.[ 1 , 31 ]

Source of Support: Nil

Conflict of Interest: Nil.

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