The Literature Review

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1.  Explore, select, then focus on a topic.

a.  This is the beginning of your question formation, research question, or hypothesis.
b.  Look at “recommendations for further research” in the conclusions of articles or other items.
c.  Use this to formulate your goal or objective of the review.

2.  Prepare for your search.

a.  Identify information sources for your topic and field:  library and information resources, organizations, special collections or archives, etc.
b.  Consider other fields that also study your topic.  Some topics may be studied by multiple disciplines (e.g., aging can be studied in the fields of medicine, psychology and social work, and from their frame of reference).
c.  Familiarize yourself with your organization’s library or information services, including interlibrary loan or document delivery.
d.  Choose keywords and search strategy:  terminology, synonyms, and combining terms (Boolean Operators AND, OR, NOT).
e.  Read other literature reviews of your topics if available.

2(i).  (For Systematic Reviews or Meta-Analyses)  Select your inclusion / pre-selection criteria to identify the types of studies that will be most relevant to the review.

a.  Decide on the following to create your inclusion criteria:

• Patient, population, or people who were studied.
• Methodology:  type of study design or method.
• Data and Statistics:  the collected data and statistics used to analyze them.
• Time range of when a study was done or published.

b.  Some disciplines, especially in the heath or human services, may use the PICO(T) or something similar to identify their inclusion criteria.

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3. Start your search.

a.  Keep track of your search strategies and results.
b.  Skim, scan, read, or annotate what you find.
c.  Try chain or citation searching to find additional documents.  This is also known as pearl mining/ growing, citation analysis, mining, or reference searching.
d.  Manual or hand searching:  visit the stacks or your journal’s online version.  Also, browse, flip or skim through publications or journals on your topic.
e.  Search alerts:  create a personal account in library databases, search engines and journal packages to get notifications.

• Saved searches:  many indexes and databases have features that will send alerts when new publications are available on your saved searches.
• Table of content (TOC) alerts:  most journals and other publications will send the table of contents for their upcoming issues, which is good for locating the most current information or scholarly works.
• Citation alerts:  when a work is cited, an alert can be sent that shows it has been used, which also can provide current or new information on a topic.

3(i).  (For Systematic Reviews or Meta-Analyses) Use a guideline and document your searches and protocol.

a.  Refer to a systematic review or meta-analysis guidelines such as PRISMA or one that applies to your discipline.

b.  Many published systematic reviews will document some or all of their searches.  This will include the search terms used, the index or database fields utilized in the search, and the number of results by each search.

c.  These types of reviews will often utilize a flowchart to demonstrate how many studies were included or excluded based on their inclusion criteria and further review of their content, and lead to a final number of selected studies.

d.  Select a repository to submit your systematic review protocol.  Some authors will register theirs in PROSPERO or similar ones.

4.  Organize your documents, data, and information.

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5. Survey and review what is found.

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Time and Rigor. 

There typically isn't a set amount of time for searching to determine when to stop less rigorous literature reviews like scoping, state-of-the-art or -science, or narrative reviews.  Reviews with higher levels of vigor, systematic reviews and meta-analyses, may take anywhere between 8 to 18 months or more complete. 

Points to Consider. 

The number of publications located usually won't indicate when to stop unless your review or assignment requirements specify this.  To summarize our conversations with professors and graduate students, and to draw conclusions from our own literature reviews, we suggest considering these points to decide when to finish your search:

• Repetition of results with various searches.  If your search results become repetitive or continue to give the same publications after using various strategies, keywords, and search engines, you may have exhausted your search.

• Sources Used for Search.  Did you search the standard information sources in your subject area?  Searches were done using standard information sources for your field (e.g., PsycInfo for psychology) and also general library sources (FAU Libraries' OneSearch). 

• Amount of time spent and strategy used in your searches.  Did you use both keywords (also known as natural language searching or using everyday words) and controlled vocabulary in your search strategy?  Using both approaches ensures you've done a thorough search.

• Your search includes current or recent publications.  Has your search included newer studies or recently published or created works?

• Amount and quality of articles/ evidence.  Have you located strong or well-designed studies in your area?  Are the results of the studies valid or reliable? 

• Being able to identify seminal works and authorities on topic.  Have you found important or highly cited articles on your topic?  Can you identify experts on your topic and their publications?  Do you know which institutions or organizations specialize on your topic? 

• Feedback from your advisor, colleagues, etc.  Let them know your search strategy and what you are finding, and then ask for suggestions to your search.