Evidence Syntheses (Scoping, systematic, & other types of reviews)

PICO is a good framework to help clarify your systematic review question.

P -  Patient, Population or Problem: What are the important characteristics of the patients &/or problem?

I -  Intervention:  What you plan to do for the patient or problem?

C - Comparison: What, if anything, is the alternative to the intervention?

O - Outcome:  What is the outcome that you would like to measure?

Beyond PICO: the SPIDER tool for qualitative evidence synthesis.

5-SPICE: the application of an original framework for community health worker program design, quality improvement and research agenda setting.

Conducting preliminary, exploratory searching is an important part of any literature review.  While there is often a desire to quickly begin crafting a final search for a review question, spending time on preliminary searches is crucial for your search.

Why?

• Determines what others have written on your topic. Has a review already been conducted? If so, how will yours differ?
• Assists in determining search strategies: Reviewing other strategies can help you harvest relevant terminology to create your own structured and sensitive searches.
• Identifies "sample set" of articles: This "sample set" of articles are articles that should appear in the final search. They are also used to validate the final search strategy. 

How?

• Conduct basic searches and examine relevant articles: Looking at terminology in titles and abstracts to identify synonyms, as well as MeSH terms.
• Related Citations: Open relevant records in PubMed and examine related citations
• Citation Tracking:  Take relevant articles and use Scopus or other citation tracking tool to see where it has been recently cited.

Sentinel articles

• Create a subset of articles that should show up in the search, to validate the final search strategy
• https://rmit.libguides.com/c.php?g=724535&p=5191553#s-lg-box-17010012

A well constructed search strategy is the core of your evidence synthesis and will be reported on in the methods section of your paper. The search strategy retrieves the majority of the studies you will assess for eligibility & inclusion. The quality of the search strategy also affects what items may have been missed. Informationists can be partners in this process.

For an evidence synthesis, it is important to broaden your search to maximize the retrieval of relevant results.

Use keywords:  How other people might describe a topic?

Identify the appropriate index terms (subject headings) for your topic.

• Index terms differ by database (MeSH, or Medical Subject Headings, Emtree terms, Subject headings) are assigned by experts based on the article's content.
• Check the indexing of sentinel articles (3-6 articles that are fundamental to your topic).  Sentinel articles can also be used to  test your search results.

Include spelling variations (e.g., behavior, behaviour). 

Both types of search terms are useful & both should be used in your search.

Keywords help to broaden your results. They will be searched for at least in journal titles, author names, article titles, & article abstracts. They can also be tagged to search all text.

Index/subject terms help to focus your search appropriately, looking for items that have had a specific term applied by an indexer.

Boolean operators let you combine search terms in specific ways to broaden or narrow your results.

An example of a search string for one concept in a systematic review.

In this example from a PubMed search, [mh] = MeSH & [tiab] = Title/Abstract, a more focused version of a keyword search.

A typical database search limit allows you to narrow results so that you retrieve articles that are most relevant to your research question. Limit types vary by database & include: