How to read a database search strategy

Author: Pauline Goodlad,
Librarian, John Spalding Library, 
Wrexham Maelor Hospital

One of the tips that Librarians often give out is to look at published search strategies for inspiration for developing your own search strategy. It might be that a Librarian has done a search for you and has sent you a copy of their strategy for your information. But do you know what you are looking at? This guide is designed to help you know what to look out for.

Firstly, it is important that the search strategy matches the research/clinical question. The following examples are based on the question “Does listening to music preoperatively reduce anxiety?”  (Walker and McNaughton, 2018). This question can be broken down into its PICO elements.

Population = preoperative patient.

Intervention = listening to music.

Comparison = not applicable.

Outcome = reduction in anxiety.

In these strategies, look to see which lines correspond to which part of the question. Have a look to see how they have been combined with Boolean operators. Synonyms and related terms should be combined with OR.  Combining concepts together should be done with AND.

Have a look to see whether the search terms are subject headings or keyword (free text) searches. The notation for this can vary across different databases.

Where you see keyword searches, have a look to see whether commands for truncation, wild cards or proximity have been used.

If you would like a refresher on some of these aspects of literature searching, then check out these bite sized videos on Boolean searching, Database searching tips, and Subject Headings.

Remember, if in doubt, get in touch with a Librarian! You can find the details of your local librarian here: https://www.nhswls.org/contactyourlibrary

Reference

Walker, J. C., & McNaughton, A. (2018). Does listening to music preoperatively reduce anxiety? An evidence-based practice process for novice researchers. British journal of nursing, 27(21), 1250-1254.

Worked Examples

The following section includes worked examples of how to pick out the details from search strategies in Medline (OVID) and Cinahl (EBSCOHost) – enabling you to understand the notations from different databases (or even user-interfaces and platforms) and how to identify the terms that match the elements of a question. Please note that these are detailed search strategies and you may find in published papers that they only list the terms used to search. This is only partly helpful as you can’t fully reproduce these searches without knowing the full details. However, it may still help you to identify relevant keywords. 

The examples below have been exported from the relevant databases and tidied up to make them easier to read.

If you want to export your own search strategies from a database, you can ask your local health librarian for assistance.

MEDLINE search strategy example

Things to note in the MEDLINE search strategy:

• The platform (Ovid) and database (MEDLINE) are listed.
• The numbers at the end of each line represent hits in the database.
• The first 3 lines correspond to the population group. The terms have been combined using OR in line 4.
• Lines 1 and 2 are subject headings (MeSH), indicated by the symbol “/” after the term.
• Line 3 is a keyword search across the mp (multipurpose) fields. This is a default setting on the Ovid platform for keyword searches.
• The “*” symbol after the keywords is a truncation command (it will bring back results with multiple endings, e.g. preoperative or preoperational).
• Lines 5 and 6 are the search terms corresponding to the intervention. They have been combined in line 7.
• Lines 8, 9 and 10 are the search terms corresponding to the outcome. They have been combined in line 11.
• Line 8 is a subject heading search. The “exp” notation means that this term was exploded (to include narrower terms). The “*” notation means that this term was focused (to only include major subject headings).
• Line 9 is also a subject heading, but only includes the subheadings “Prevention & Control” and “Surgery” for the subject heading.
• Line 10 is a keyword search. These keywords have just been searched within the title (ti), abstract (ab) and the author Keyword (kf) fields.
• Line 12 are the three elements/concepts combined using AND.
• Line 13 shows that the search was limited by language and date.

CINAHL search strategy example 

[Update: August 2026]   *Please note that the XB field code is a new addition to Cinahl. You may come across older searches that use TI and AB, the individual field codes for title and abstract.

© 2024. This work is openly licensed via CC BY-NC-ND 4.0