Literature Reviews: The basics
What is a literature review?
A literature review is an overview and critical evaluation of the literature on a specific topic. It identifies, summarises and synthesises current knowledge, whilst also establishing gaps in understanding.
Why conduct a literature review?
Literature reviews tend to be carried out in order to develop a deeper level of understanding of a specific topic prior to conducting new research in the field. Identifying issues, debates and gaps in existing knowledge is important for demonstrating that you are contributing something new and original to the field, underlining the value of and need for your research.
Importantly for those of you conducting a literature review as part of a wider project, such as a dissertation or thesis, the literature review also provides you with material with which to compare your own findings in the discussion section of your work. For information on the different types of literature reviews, see my blog: ‘Reviews of the literature: Types and distinctions’.
How do I carry out a literature review?
There are several steps you can take to guide you through conducting a literature review.
1. Define the topic or research question
You need to have a clear idea of what exactly you are looking for to provide you with a focus for your review, so the first step is to define your topic or research question.
It can help to undertake a preliminary search of the topic, using a basic Google search or encyclopaedias such as Wikipedia. This can provide you with basic facts which may be useful for gauging the topic, keywords, terms, issues, concepts, key authors, and potential references. Starting in this way can be useful as it allows you to jot down ideas, make plans and determine the direction of your research.
It is important to note that Wikipedia should not be included in the actual literature review. With open sources like Wikipedia, there are issues surrounding accuracy and reliability as anyone can edit the material and it can be difficult to check the authority of authors.
Once you have your key research question(s) in mind, this should guide your research and help you to determine what is currently known about your particular topic. Here, you will be asking yourself what you need to know in order to answer the research question(s) you have set. What have previous scholars already researched and found on this topic and what new knowledge do we need?
2. Decide on key terms
The second step is to write down keywords that you will use in your search which relate to the topic or research question. You will be able to use these in different combinations when conducting your search. The keywords might be as straightforward as the words you use in your research question, but you can expand your list by selecting synonyms, or alternative phrases for your topic, to make sure you include a broad range of keywords. Your preliminary research on the topic should also have helped you to identify useful terms.
3. Choose appropriate databases and data sources
When deciding where to start searching, it is often helpful to begin with the university library as they tend to have discipline-specific areas which will help you to identify electronic databases and other useful sources.
Electronic databases, such as ProQuest, are a good starting point. They provide access to scholarly articles and tend to be subject-specific. You can search widely or use filters to refine the search.
Other sources of information include books, journals, reports, White papers and policy briefs, conference papers and websites. You can go directly to these sources and search within them.
With websites, remember to assess the credibility of the source, which you can do by looking at the URLs (Uniform Resource Locations). Academic sites have ‘.ac’, government sites use ‘.gov’ and educational sites use ‘.edu’. Sometimes the country of origin is also indicated e.g., ‘.uk’ or ‘au’.
‘Google Scholar’ is another useful tool for locating academic records and is more reliable than Google for obtaining academic sources.
Non-academic sources such as magazines, blogs, and newspapers should largely be avoided within literature reviews.
4. Conduct the searches
Once you have your key terms, and you have decided where to search, you can begin to look for sources.
Depending on the number of sources that you find when searching, you may need to narrow and refine the search to ensure that you do not end up with thousands of sources. As Shaw (2010: 43-44) explains, with a literature search, the aim is to:
…find a balance between comprehensiveness and specificity – be as comprehensive as possible whilst narrowing the search as much as possible to increase the chances of records being relevant.
You can use Boolean operators (‘and’, ‘or’, ‘not’) to narrow or broaden the search, as well as quotation marks.
Filters can also be used to narrow the search using different criteria such as date range, source type and subject area, among many others.
If you still have a large number of sources, you may need to go through these for relevance by looking at the titles and abstracts. Abstracts of journal articles tend to include particular details such as research purpose, methods, findings and conclusions, which can help you to determine whether or not a source is appropriate for your study. This can save a lot of time. Where they do not, you may need to skim other sections of the journal article to locate this type of information. It should not be necessary, however, to read the entire article.
If you filter the search and find that you get too few sources, you may assume that this is because there is little on this topic. You can check by broadening the search once again, maybe by removing one of the words and checking the titles and abstracts of the identified sources. If you find that your specific topic still does not turn up in the review, you can conclude that your assumption was correct.
You can stop the search when you reach saturation, often considered to reflect when the same authors and studies frequently recur in your searches. You should also ensure that your search includes a range of contemporary research and established or classic studies.
5. Document the details
In this step, there are three important types of details that you should document:
1. The database search:
Depending on the type of review you are conducting, the level of recording you keep for this stage will vary, but you should still document everything clearly in case you need to repeat the search later, or simply to be able to show the approach you have taken if required to include these details.
Getting into the habit of keeping accurate records will save you a lot of time later on, especially as you might forget what searches you have conducted and end up carrying them out again!
So, take a little time to write down the date you searched, the databases, the keywords used, the number of sources, and any filters you applied when searching.
2. The source details or citation:
Make sure you keep the referencing details for each source you use too, as hunting for these later when constructing bibliographies can waste a lot of time. Try to get into the habit of writing the bibliographic details down every time you read and take notes from a source.
These include the title and author of the article or book chapter, the year of publication, the title of the book or journal and the editor(s), the publisher and place of publishing. Citation management software is available for this task, which may speed things up for you. Remember to also note down the page numbers for quotations, statistics and key concepts and website addresses for web sources, as well as the date you accessed them.
3. The source content:
You should keep a good record of what the sources showed, so make summaries for yourself. This is a very important step as this is where you begin to evaluate the source content.
a. Initial questions to ask yourself here might include:
i. What was the aim or purpose of the study? What is the research question?
ii. What methods did they use? What approach did they adopt and what sample did they use?
iii. Is the material primary (based on their own findings) or secondary (based on other primary sources)? If secondary, is the analysis appropriate and have original sources been cited?
iv. What are the findings?
v. What contribution does the study make to the field?
vi. What are the limitations of the study?
vii. Is the information relevant for my own needs?
b. Evaluating the content on a more in-depth level will require you to dig a little deeper:
i. How reliable are the study claims and findings? How have others reviewed the methods and the findings of this study?
ii. How accurate is the information? Are there errors?
iii. Has the source been peer reviewed?
iv. Have the claims been verified or supported elsewhere? Have the findings been undermined or challenged by others?
v. How credible is the source? Who are the authors? Where are they based?
vi. How reputable is the source? What type of source is it?
vii. How current is the study and the information provided? Is it out of date?
viii. What is the presentation of the source like? Is it easy to follow and logically presented?
ix. What is the intended audience of the source?
6. Demonstrate your knowledge
In this final stage, you will be pulling together everything you have learned and presenting that information in a well-organised, structured fashion, often constructed around themes and based on your evaluation of the literature.
The aim here is to synthesise the material and present it in a way that communicates the topic to the reader as clearly as possible and is focused on your research question. You should be able to show what is currently known about this topic and where key gaps lie, but in a way that is easily accessible for the reader and does not simply convey a list of sources on the topic.
Where can I find out more?
There are many great sources available on conducting literature reviews, so this list is just a starting point, but some really useful texts include:
Clark, T., Foster, L. and Bryman, A. (2019) How to do your Social Research Project or Dissertation. Oxford: Oxford University Press.
Greetham, B. (2020) How to Write Your Literature Review. London: MacMillan Education Limited.
Hart, C. (2018) Doing a Literature Review: Releasing the Social Science Research Imagination. 2nd Edition. London: Sage Publications.
Jesson, J., Matheson, L. and Lacey, F. (2011) Doing your literature review: Traditional and systematic techniques. London: Sage.
Machi, L.A. and McEvoy, B.T. (2022) The Literature Review: Six Steps to Success. 4th Edition. California: Corwin.
Randolph, J. (2009). A Guide to Writing the Dissertation Literature Review. Practical Assessment, Research and Evaluation 14(13): 1-13.
Ridley, D. (2008) The Literature Review: A Step-by-Step Guide for Students. 2nd Edition. London: Sage.
Shaw, R. L. (2010). Conducting literature reviews. In M. Forrester (Ed.), Doing qualitative research in psychology: a practical guide (pp. 39-56). London: Sage.