Students often ask me how many sources they need in their literature review. The short answer is, “It depends.” It depends on your topic, the nature of your research project, your level of scholarship, and a number of other factors.
An article from Canberra University (http://www.canberra.edu.au/studyskills/writing/literature) suggests:
- Undergraduate review: 5-20 titles depending on level
- Honours dissertation: 20+ titles
- Master’s thesis: 40+ titles
- Doctoral thesis: 50+ titles
Another strategy I learned somewhere along the way that I now share with my students is this:
If your literature review is one section of a larger research paper, thesis or dissertation
Minimum number of sources = number of pages in the body of your entire paper (exclusive of title page, abstract, appendices and references)
Example: A paper that has 10 pages of content (the body of the paper) needs at least 10 sources in its literature review.
A thesis of 100 pages (in the body) includes at least 100 sources.
If your literature review is a stand-alone document
Minimum number of sources = 3 times the number of pages in the body of your paper (exclusive of title page, abstract, appendices and references)
Example: A stand-alone literature review that has 10 pages of content (the body of the paper) should examine at least 30 sources.
These are not hard and fast rules by any means. Also, it is worth mentioning that as students and scholars who care about the quality of our work, we want to aim to raise the bar, not simply meet a minimum suggested standard. What these guidelines are suggesting is that you don’t aim for any less. If you do, your search for relevant literature in your field may be incomplete and you need to keep digging. Of course, your sources have to be relevant to your topic, too.
Not every scholar or academic supervisor would agree with the guidelines I offer here, criticizing them as being too reductionist or simplistic. My point isn’t to offer a black and white rule or open theoretical debate for which there can be no clear solution, but rather to offer a straight forward and practical answer to a question that academics often respond to in an ambiguous way, leaving students frustrated, exasperated and anxious about how to go conduct their literature review.
When in doubt, talk with your own instructor or supervisor, asking them what their expectations are. (Don’t be surprised though, if you get an answer that is vague, like, “It depends…”)
Remember: Aim for quality over quality… and to do a quality literature review, you need to have a substantive quantity of sources.
Here are some of my favourite resources to help you write your literature review:
University of Toronto – http://www.writing.utoronto.ca/advice/specific-types-of-writing/literature-review
U Conn – http://classguides.lib.uconn.edu/content.php?pid=239974&sid=1980274
University of Leicester – http://www2.le.ac.uk/offices/ld/resources/writing/writing-resources/literature-review
Queensland Univeristy of Technology – http://www.citewrite.qut.edu.au/write/litreview.jsp
Birmingham City University – http://library.bcu.ac.uk/learner/writingguides/1.04.htm
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Sarah Elaine Eaton is a faculty member in the Werklund School of Education, University of Calgary, Canada.
This entry was posted on Wednesday, February 19th, 2014 at 12:54 pm and is filed under education, research. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.
As alluded to in the comments, there is no generic "right" answer: the number will depend strongly on the nature of your thesis, the state of the literature related to it, and your personal scholastic style. Nevertheless, in the spirit of engineering approximations, I will supply you with some rough guidelines.
As a lower bound, I would be startled if it was possible to place most theses within the context of pre-existing work in less than about 20 references. In certain contexts such as an obscure corner of pure mathematics perhaps this might be possible, but in most cases work does not take place in a vacuum, and other people will have either used similar techniques or cared about similar problems in the past.
As an upper bound, I would be concerned with a thesis with on the order of 200 or more references that the student hasn't been doing enough work on their own original research and has been investing too much time and energy in building a literature review, rather than a thesis. Again, there will likely be cases where a thesis with an extremely high number of references would be reasonable, but these are likely to be unusual.
Notice the extremely wide range and suspiciously round numbers in my estimates: really there is no "right" answer for how many there should be in general, but perhaps these will help with some initial first impressions in one's thinking.