The review of the literature is an attempt to summarize the relevant field and to help justify the need for the proposed research. Your treatment of the literature should be a critical analysis of what has been published, not a passive one (i.e., not just who did what when). In writing the literature review, your purpose is to convey to your reader what knowledge and ideas have been established on a topic, and what their strengths and weaknesses are. As a piece of writing, the literature review must be defined by a guiding concept (e.g., your research objective, the problem or issue you are discussing, or your argumentative thesis). It is not just a descriptive list of the material available or a set of summaries.
Develop a Search Strategy.
- Formulate a clear research question.
- Use the PICO method, if appropriate.
- Identify the key concepts for your research question and transfer them to a concept table.
- Develop search terms and keywords in order to identify as many relevant peer-review publications as possible:
- Controlled Vocabulary:
- Use Emtree to find the suggested Emtree Subject Headings for your topic.
- Use the MeSH thesaurus to find MeSH terms appropriate to your search.
- Free terms:
- Copy your search strategy into PubReminer.
- Use Embase Index Miner to see additional keywords associated with your search strategy.
- Controlled Vocabulary:
- Build a search phrase by using Boolean operators (i.e., or, and, not).
- Search each phrase combination one at a time.
- Use the advanced search platforms on the major web resources to structure Boolean searches.
- Am I searching the correct resources?
- Search Dykes Library Databases: PubMed, CINAHL, Embase, or Web of Science.
- Almost any review in biomedicine should include a search of Medline via either PubMed or Ovid platforms.
- Research librarians at Dykes Library recommend using Ovid Medline.
- The library has many specialized resources in its A-Z database list.
In many cases, searching trial or systematic review registries such as Cochrane Library will also be valuable. Consult with the librarians to determine you are searching comprehensively.
Consider your review strategy.
- How good was my information seeking?
- Your search in the databases should be as broad as possible given time and resource constraints. Downloading several hundred titles from the databases into an Endnote library and only using a small percentage is preferable to missing relevant literature.
- Systematic literature reviews often have inclusion rates below 5% of search results.
- Have I critically analyzed the literature I use?
- Do I follow through a set of concepts and questions, comparing items to each other in the ways they deal with them? Instead of just listing and summarizing items, do I assess them, discussing strengths and weaknesses?
- Have I cited and discussed studies contrary to my perspective?
- Will the reader find my literature review relevant, appropriate, and useful?
- PubMed and Embase report how many times an article has been cited.
- Use Web of Science to sort a list of results by Times Cited. Make sure you are familiar with the highly cited work in the field.
How to Cite Literature.
- Your target journal will have a specific citation strategy that you will need to follow.
- Endnote make this easy with Cite-While-You-Write functions through a free Microsoft Word Add-in. Use specific journal output styles and manuscript templates made available through Endnote or Zotero.
- Use Endnote or Zotero to store and organize citation information and full-text articles.
- Do not Copy and Paste without a Citation!
- It is very important that you give credit to the source of any information or ideas that you present in your manuscript. The source of the information or ideas must be credited directly in the text at the end of the relevant sentence.