Researching and Writing a Literature Review
A literature review demonstrates that you have read around your topic and have a broad understanding of previous research, including its limitations.
In the literature review, you summarise the main viewpoints and important facts that you encountered in your reading as they relate to your chosen topic. You will also use the literature review to justify the value of doing research on your topic by showing what is already known, what is not yet known, and how it is relevant.
Your literature review should not simply be descriptive but should also provide a critical analysis of the body of work, and demonstrate that you understand how it fits together as a whole and how your own research fits with previous studies.
A key aspect of a literature review is what sources you select to include, and which you exclude.
Thanks to the internet, literature searches are now relatively easy, and can be done from the comfort of your own laptop without needing to go anywhere near a library.
However, a word of warning is in order here. The ease with which anybody can access and publish to the internet means that many items published online have not been scrutinised by anybody other than the author.
In other words, content has not necessarily been checked, you have no way of knowing whether the author’s facts and claims are at all accurate and you could easily land yourself in trouble by blindly following or citing from online sources.
Furthermore, because items on the internet are frequently changed, you may find that something you read yesterday is no longer available in the same form today. However, internet sources can be very useful for up-to-date information, especially current affairs or ongoing or very recent research.
Blogs and sites like the encyclopaedia Wikipedia are particularly prone to these problems. For these reasons, a general rule of thumb is that you should only rely on internet resources from the websites of organisations whose information you already know to be reputable, like SkillsYouNeed.
Do not underestimate how much physical libraries and librarians may be able to help you.
Librarians are usually hugely experienced in using all the search tools and databases, and can often show you much quicker ways of doing things, as well as tips and tricks to help you refine your search.
Furthermore, libraries may have copies of books and academic journals that are not available online. So a trip to your library may prove to be very helpful.
If you haven’t already done so, get yourself an ATHENS account through your university and/or school library. Spend time working out which of the available databases are going to be most useful for your topic, including asking the librarians for advice.
A simple way to get started with finding appropriate materials is simply to ask people who are likely to know.
You might for example ask your tutor or supervisor, or an expert or practitioner working on your chosen topic. Often, they will be able to give you some very helpful ideas about where to begin your reading.
However, be aware that some professionals may find constant requests for information intrudes on their time. Always be courteous and sensitive to the level of demand you may be making on someone’s time.
See our page: Sources of Information for more about the types of resources that you might use and how to access them.
Choosing and Refining your Search Terms
Your search terms are one of the most important elements of finding the right sources for your research project and developing them is an ongoing process.
It’s a good idea to start with a phrase that you think others will have used about the topic, perhaps that you have identified from your lectures and/or earlier study. You will probably find that your first few searches don’t turn up much that’s useful.
Use the one or two articles that you find that are on the right lines to identify alternative search terms, and continue to search until you turn up useful articles.
You can also use a tool such as Google Adword Keyword Research Tool to identify phrases and keywords that are similar to your chosen term(s). This tool is usually used by internet marketing professionals to help them find keywords similar to their own but can be useful for academic research too.
If you’re really struggling to find articles on the right topic, but you’re certain that they must be out there, drop your supervisor a note asking about possible search terms. Tell them what you’ve already used, and ask them for a few alternatives to get you started. However, this should be a last resort, as you don’t want to demonstrate your ignorance too obviously!
Finally, keep searching. You need to read a lot of sources to find the most relevant and will probably end up discarding more than half of what you read. Use abstracts to decide which articles are worth reading, and don’t read those that aren’t relevant: keep checking back to your research questions and decide whether each article is useful. If not, move on.
Your literature review should not only show that you have been reading a range of materials related to your topic, but also that you have been reading them critically and have thought about the wider contexts and how they apply to your own area of research.
Critical reading is a skill that, like any other skill, is acquired with practice.
In essence, reading critically means that you do not take the claims at face value: you question the basis for claims, why the author may have done and said things in the particular way he or she did, what the wider context is, and whose interests are being served by the claims you encounter.
See our page, Critical Reading for more information.
How Many Sources?
Your university or college supervisor will be able to give you an idea of how many sources you should include in your literature review.
You will probably need to read at least double that number to find enough that are suitable for inclusion. You should also try to find several different sorts of sources: books, journal articles, dissertations, conference papers, working papers, and so on.
You need to make sure that you identify the key texts for the subject. Check a few references, and see which texts are cited most often, or ask the librarians how to use the databases to check how often each article is cited. A good way to identify when you have read enough is if your reading keeps turning up the same points and you’re not learning anything new.
A Note on Dates
There are some theories or articles which are so important in a particular field that they need to be cited, however long ago they were originally published. But those apart, you should generally prefer more recent sources published in the last five or ten years. As a rough guide, the balance of publication dates should be about two thirds from the last 10 years, and no more than one third older than that.
Writing your Literature Review
For general advice about academic writing, see our page on Writing an Essay.
In general, your literature review should start with one or two broad paragraphs, demonstrating your understanding of the breadth of your area of study.
You should then discuss the literature that deals with your area of research and, finally, consider and critique the studies that are most directly relevant.
You should spend most time on the latter.
Writing your literature review should be an iterative process.
The best way to do it is probably to summarise each source as you go along, referencing it carefully, and grouping your sources by themes.
You will almost certainly find that the themes develop as you go along, and so do your search terms. Use headings to store your summaries and then write a more polished section under that heading when you have enough sources to be able to ‘compare and contrast’ opposing views, and particularly to draw out areas where there is disagreement and/or conflicting evidence as these are the most fruitful for further research.
Where there are gaps, you can then go back and search for more sources on that area. The best literature reviews are not only descriptive, but draw together similar thinking and provide a critical analysis of the previous research, including highlighting really good studies, or identifying flaws and gaps.
To make sure that you carrying out a critical analysis, make sure that you ask yourself the question ‘Do I agree with this viewpoint? Why?’, and also consider whether the methods used are strong or weak and why. This will also help you to decide on your own methodology.
Another way of checking whether you are evaluating or merely describing is to look at whether you have discussed work chronologically (likely to be descriptive) or in terms of whether there is general agreement on a topic (much more likely to be evaluative).
Checklist of Questions for Critical Reading
Ask yourself the following questions to decide whether or not a particular piece of work is worth including in your literature review.
- Who is the author? What can I find out about him/her? Has he/she written other books, articles etc.?
- What is the author’s position in the research process, e.g., gender, class, politics, life experience, relationship to research participants?
- Where and when was the document produced? What type of document is it?
- Is it reporting original research that the author has done, or is it presenting second-hand information about a topic?
- Is it formal or informal?
- Is it 'authoritative' (e.g., academic, scientific) or 'popular' (newspaper or magazine article)?
- How has it been produced? Is it glossy, with lots of pictures, diagrams, etc.?
- If it is contained on a website, is the website from a reputable organisation, or is the document drawn from some other reputable source?
- What is being said?
- What is not being said?
- How is the argument presented? Why?
- What use has been made of diagrams, pictures etc.?
- Who was or is the intended audience?
- Whose interests are being served by this message? Are there political implications, for instance?
- What evidence is presented to support the claims that are made?
- Does the evidence actually support the claims? Is the evidence presented in enough detail for you to make up your own mind whether you agree with the claims?
- Are there errors or inconsistencies?
- What is the significance to my topic and the research that I wish to carry out?
Your literature review should also demonstrate how your study does or will relate to previous work, and how it either fills gaps, or responds to calls for further work.
Your literature review will help you to refine your research question. It should also help you to explain how your methodology fits with previous work, and help you to identify and evaluate possible research methods.
A Note on Tense
When you are describing someone’s findings or opinions, it is probably best to use the past tense.
“Jones (2001) argued that…”.
Many authors of academic papers prefer the present tense when describing opinions or views (“Jones (2001) argues that…”). However, it is always possible that Jones has subsequently changed his/her view, and therefore the past tense is preferable.
The past tense is always going to be correct for something that was expressed in the past; the present tense may no longer be true.
Citations and References
Your university will almost certainly have a preferred style for citations and references that you will need to use. Make sure you understand how this works before you start writing your literature review and use it consistently throughout.
Keep your references up to date as you go, and make sure that you always cite the reference as you write: it’s much easier than trying to build a reference list at the end.
See our page on Academic Referencing for more information
For scientific subjects, Vancouver (numerical) referencing is often preferred.
However, it is much harder to check that your references are correct using this system. It is therefore better to use a (name, date) system of citations until you are certain that you have finished revising the document.
Alternatively, use a system of end-notes which will automatically update the numbering if you move a citation as you will otherwise end up hopelessly confused.
Draft, Draft and Redraft
Finally, once you have written each section by theme, go back and read the whole thing to check that the sections flow logically one from another, and that the whole literature review reads sensibly and coherently.
As with any essay or extended piece of writing, editing and redrafting will improve the quality of your writing, as will asking someone else to read it over and check for errors or inconsistencies.
You should also do a search to check for consistent use of British or American spellings (-ise and -ize, for example), double spaces after words, and double/single inverted commas around quotations. You might think such details are less important than the content, but the marker may not share your view.