Whether you are doing a topic summary for a term paper, a state-of-the-art survey, or a full literature review for a thesis or article, there are some common expectations that your professors have for graduate student work. They are not looking for you to simply describe some papers that you have read on the topic, one after the other. What they do expect is:
You want to be organized from the start when doing a literature review, especially for a project that will take a long time.
When you actually read the papers that you find, most people take a staged approach to save time:
What does annotating mean? Take very short notes (on paper or digital) of the most important findings and/or highlight important lines in the paper. You can highlight and annotate the PDF file if you want, or in your citation manager. You don't usually need to summarize the whole article - instead focus on what is important for your research or review, and write it in your own words. This could be the
One technique is to create a concept map or 'mind map' showing the relationships or groupings of the key papers on your topic, with short labels. This way, you can try out different options for how to structure your paper and see which one makes the most sense. You can do this on paper:
You can also do this digitally, using a mind-mapping website. There are some easy-to-use, free tools that are available now. Two that I have used are Coggle and Miro. You can also just sketch on paper.
Created using Coggle.it, based on a chart in Huang, H. (2018). Methods for Rolling Element Bearing Fault Diagnosis under Constant and Time-varying Rotational Speed Conditions (Ph.D. Thesis, University of Ottawa). http://dx.doi.org/10.20381/ruor-21835
Image: Pacheco-Vega, R. (2016, June 15). How to do a literature review: Citation tracing, concept saturation and results’ mind-mapping. Retrieved from http://www.raulpacheco.org/2016/06/how-to-do-a-literature-review-citation-tracing-concept-saturation-and-results-mind-mapping/
After you have taken notes on individual articles, it can be very helpful to create a chart with key variables that seem important. Not every article will cover the same material. But there should be some common factors, and some differences between them. This chart is called a synthesis matrix.
Example of a 'synthesis matrix'
cadmium telluride (p. 312)
copper-indium selenide (p. 1209)
polycrystalline silicon ( 54)
|Efficiency of solar cell
12% under STP (p. 65)
15% (p. 1215)
22% at 45 deg. C ( 56)
|Use of thin-film solar cells
depending on application, can be preferred (p. 320)
cannot be used above 50 degrees Celsius (p. 1213)
not preferred - cost to efficiency of silicon is higher (p. 59)
Source: University of Western Ontario Library (n.d.). “Writing your literature review”. https://guides.lib.uwo.ca/mme9642/litreview
See this blog post by researcher Raul Pacheco-Vega for another example of how he does this.
This chart can help you decide how to organize your review. If it's a very short review, some people write it chronologically - they describe how the topic evolved, one paper at a time. But if you have more than 10 papers, this is not a good approach. Instead, it is best to organize your review thematically. In this approach, you group the papers into several groups or themes, and discuss each theme in a separate section. Usually the groups are major methods of tackling the problem, or concepts, or techniques.
In each section of your paper, you introduce the theme, and then discuss and compare the papers in the group. Using this approach lets you show that you have not just read the papers, but have understood the topic as a whole, and can synthesize the literature.
For example, this paper co-authored by Ping Li, a Civil Engineering PhD graduate of uOttawa, organizes the papers into three categories: ones that used a 'traditional' approach; ones based on characterization of the soil microstructure, and ones that also incorporate soil mechanics. The strengths and weaknesses of category are discussed, and in the conclusion, the authors recommend approaches for future studies.
You can often include a form of a synthesis chart in your paper or thesis, as a visual summary of your lit review. This is part of a chart included in a Masters' thesis in Computer Science from uOttawa.
From Le Page, S. (2019). Understanding the Phishing Ecosystem (M.Sc. Thesis, University of Ottawa). http://dx.doi.org/10.20381/ruor-23629