What is a Literature Review and What is its Purpose?
A literature review is a survey of scholarly sources on a specific topic. Through a literature review, a researcher will identify related research that has been accomplished, and may explore appropriate methodology for that research. It provides an overview of current knowledge, allowing you to identify relevant theories, methods, and gaps in the existing research.
You need to provide context for your research in relation to what is already known. What is the existing knowledge and where does your research sit within this context? How is your project unique from other similar projects? 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.
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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Once you have you have clearly defined your topic and have your keywords/phrases ready, search a wide range of sources to find relevant literature, including: WorldCat Discovery (Library's catalog) to find books and documents, Google Scholar, and core databases in your field. Don't forget to search for technical reports, patents, and government documents too.
You can't read everything, so try this approach to make an initial decision on articles:
Read the article abstract - if it sounds related then
Read the findings, results, or summary of the research results - if it still sounds relevant, then
Go back and read the entire article
If not, discard it and move on
When you find useful book or article, check the bibliography/references to find other relevant sources. The number of of citations an article has (i.e. the number of times other authors have cited a publication) can be an indicator of its importance to the field, but beware of self-citing and ghost citations that can make an article look more critical than it is.
When you get to the point in your search that you are seeing the same articles and authors over and over, you've done a good, comprehensive search.
Step 2 - Evaluate What You Find - Is It Relevant?
As you search, be thinking about the following questions as you do your research:
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?
Step 3 - Identify Themes, Debates and Gaps in the Literature
As you do your research, 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 show how your own research will contribute to existing knowledge or how it fits into the whole.
Step 4 - Develop an Outline for Review
There are various approaches to organizing a literature review:
The simplest approach is to trace the development of the topic over time. Make sure you 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.
You can organize your literature review into subsections that address recurring, central themes or 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.
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
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.
Or Combine Approaches
You may find it helpful to combine several of these strategies, particularly if your literature review is long. For example, your overall structure might be thematic, but each theme is discussed chronologically.
Step 5: Write your 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:
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 draw connections, comparisons and contrasts between sources
Examples of Literature Reviews in the Sciences
Writing a good literature review can be tough. You might want to take a look at examples of literature reviews others have written
Girls in the physics classroom: a review of the research on the participation of girls in physics, by Patricia Murphy and Elizabeth Whitelegg. (2006) Institute of Physics, London, UK; https://oro.open.ac.uk/6499/3/Girls_and_Physics_Report.pdf
Become Familiar with your Topic - Handbooks and Specialized Encyclopedias
Finding introductory information for subject areas that are unfamiliar can help you identify appropriate search terms, help you familiarize yourself with materials and chemical properties, and help you focus on issues related to your research process
Handbooks, Encyclopedias and other multi-volume reference works can help, as can graduate level textbooks. Go to the tab Find Books, Documents & More on Your Topic in this guide for how to find these resources.
Find Literature Reviews for an In-Depth Overview
Literature reviews are particularly helpful in finding past research on a specific topic because someone else summarizes the research in an area up to a particular date, essentially doing some of your research for you, and providing some context for that research.
Some databases provide a way to limit a search to reviews in journal articles. The following databases provide access to reviews across a wide range of disciplines:
OATD.org aims to be the best possible resource for finding open access graduate theses and dissertations published around the world
Mine Article References, Use "Cited By" Features, Search Authors
When you find relevant articles, look at the bibliographies - the references the author used to write the article. This will lead you to additional sources. Some databases offer links to these references, and to articles that cite the relevant article you found. For example:
The Web of Science database allows you to link to an authors References and do a "cited reference" search on others who have cited the original article
SciFinder provides a "Citation Mapping" feature that allows you to search backward into an author's references and forward into articles that cite the original article
Google Scholar provides a "Cited By" link to articles that cite the original article
Have you found an article that is cited repeatedly or know of key individuals in the field? Use an author search to find additional sources by these experts.
Source for this Guide
Some of the materials in this guide originated from How to Write a Literature Review: Guide, Examples, & Templates, by Shona McCombes. Scribbr.com, February 22, 2019. URL: https://www.scribbr.com/dissertation/literature-review/