Evidence Synthesis in the Social Sciences

It's important to keep careful records of the finalized search strategy that you create, along with the results that that strategy yields in each database you search. After you run your finalized search strategy in each database, you must save all the results in a reference management system for later screening. Keep records of how many sources are produced from each search, as you will need to complete a flow chart of your sources and information later in the screening process. 

From PRISMA (2020): 

"Specify all databases, registers, websites, organisations, reference lists, and other sources searched or consulted to identify studies. Specify the date when each source was last searched or consulted." p.5

"Present the full search strategies for all databases, registers, and websites, including any filters and limits used." p. 6

"Describe the results of the search and selection process, from the number of records identified in the search to the number of studies included in the review, ideally using a flow diagram."  p. 18

There are many elements to crafting a comprehensive search strategy. Searching requires: 

1) Knowledge of databases being searched 

2) Understanding of boolean operators, search truncation, proximity searching, and resource fields

3) Understanding of index terms and keywords

Helpful Resources to Get You Started: 

A search strategy for the OSF example, above. 

Additionally, different databases have different syntax -- "rules" and usages for search fields, search punctuation, and search proximity indicators. See the below sections for more information on "translating" your search elements (truncation, proximity, fields) into different databases. 

Here are a few helpful tools: 

• Polyglot search tool

  The Polyglot is a tool for translating search strings across multiple databases. NOTE: many non-health science databases are not included in polyglot. 

• Database Syntax Guide

  ​Guide to translating syntax for multiple databases. From Cochrane.

Keywords and Terms Overview

This table from University of British Columbia Libraries breaks down the types of search terms and their considerations. 

Subject Headings

Subject headings like MeSH (Medical Subject Headings) are widely used in databases like PubMed or MEDLINE. Other subject heading controlled vocabularies are used to index articles in other databases.

The Importance of Using Both Keyword and Indexed Terms

From Covidence: 

"Using index terms such as MeSH and Emtree in a search can improve its performance. Indexers with subject area expertise work through databases and tag each record with subject terms from a prespecified controlled vocabulary.

This indexing can save review teams a lot of time that would otherwise be spent sifting through irrelevant records. Using index terms in your search, for example, can help you find the records that are actually about the topic of interest (tagged with the index term) but ignore those that contain only a brief mention of it (not tagged with the index term).

Indexers assign terms based on a careful read of each study, rather than whether or not the study contains certain words. So the index terms enable the retrieval of relevant records that cannot be captured by a simple search for the keyword or phrase...

Relying solely on index terms is not advisable. Doing so could miss a relevant record that for some reason (indexer’s judgment, time lag between a record being listed in a database and being indexed) has not been tagged with an index term that would enable you to retrieve it. Good search strategies include both index terms and keywords." 

Another option alongside Boolean Searching is Proximity Searching. From U Melbourne: 

"Proximity searching allows better control of the relevance of concepts by adjusting their proximity to one another. If the concepts occur close together in a sentence or paragraph, the topics are more likely to be relevant than if they are widely separated.

Most database platforms offer proximity operators to specify word order and separation.  Check the help system of the database you are using and look for proximity to find information on how to apply it correctly.

Replace # with the maximum number of words to occur between the two concepts."

Proximity Searches in Common Databases and Platforms

Fields are also used to search and procure resources based on select parts like title, author, or journal. 

This table from Johns Hopkins Medical Library breaks down field codes for several major databases and platforms.