Graduate students who are unfamiliar with what is expected of them in terms of higher-level research writing can easily get overwhelmed when it comes to their literature review. A literature review can form part of a larger project, such as a chapter in a thesis or dissertation, and it can also be a standalone project. Regardless of whether it is part of a project or a standalone work, we (your professors) expect certain kinds of sources.
We learned what kinds of sources to include in literature reviews when we were students, but we are not always so good at articulating what those expectations are. The result can be frustration for both students and professors. In this post, I have curated tips and information that I have been sharing with graduate students over the past several years.
These tips are intended to be a guideline, not a prescription. They are based on my experience and include a healthy dose of my own opinion. For example, I am adamant that students should avoid citing Wikipedia in their research writing. I am also unapologetically opposed to quotation websites where students have been known to cut and paste quotations from great thinkers such as Aristotle or Plato. In my view, quotations for research writing ought to come from original works (or in a pinch, a translation of an ancient text).
Your professors or research supervisors will have their own ideas about what kind of sources to include in your literature review, so be sure to consult with them. Here’s what I tell my students:
Most respected sources
Books, peer-reviewed scholarly or scientific journals from reputable publishers. Avoid predatory journals. At least 80% of the total number of sources in your literature review should be sources from this category.
Sources that are OK to use in moderation
Credible edited journals that may not be peer-reviewed, but are highly respected in a professional field; edited conference proceedings; papers from well-respected research institutes or think tanks. Usually, not more than 20% of your sources should come from this category.
Sources that should be used sparingly
Materials from highly reputable news agencies such as the BBC or the Washington Post or highly respected websites, such as the Mayo Clinic. It is not that these sources are not credible, but that you want your research literature review to be strongly focused on research materials. For that reason, I recommend that not more than 5% of sources come from this category.
Sources to avoid
I mentioned two of the big ones above: Wikipedia and online quotation sites. Also avoid predatory journals and any sites (including popular media) that is less reputable.
Here’s an infographic to help you make wise choices about what kind of material to include in your literature review.
If your topic has limited sources available in the research, find and analyze what you can, but avoid “padding” your literature review with non-scholarly sources.
When you are learning how to write a literature review, it can be tricky to figure out what kinds of sources to include. Remember, you want to focus on producing a review that is evidence-informed and research-based. The quantity of sources you consult may be important, but quality is definitely important.
Talk with your supervisor about their expectations and get guidance as you go along. The more you work with scholarly or scientific sources, the better you will get at writing literature reviews.
Here’s a longer essay I wrote on this topic if you are interested in reading more:
Eaton, S. E. (2018). Educational Research Literature Reviews: Understanding the Hierarchy of Sources. Calgary: University of Calgary. Retrieved from http://hdl.handle.net/1880/106406
How many sources do you need in a literature review? http://wp.me/pNAh3-1Hu
5 Websites to avoid referencing in your research papers http://wp.me/pNAh3-1IA
What’s the difference between a manuscript and an article? http://wp.me/pNAh3-1SV
How to provide peer review feedback http://wp.me/pNAh3-1qH
Template for a 10-page graduate research paper in social sciences http://wp.me/pNAh3-1s2
How to narrow down your research topic http://wp.me/pNAh3-1Xf
Dear students, It is not O.K. to cite Wikipedia as a source for scholarly articles. Sincerely, your prof. http://wp.me/pNAh3-1qx
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Sarah Elaine Eaton is a faculty member in the Werklund School of Education, University of Calgary, Canada.
Opinions are my own and do not represent those of the Werklund School of Education or the University of Calgary.