If you were researching the effectiveness of acupuncture for treating allergic rhinitis, you might begin with a research question that looks like the following.
How effective is acupuncture in treating allergic rhinitis?
This question could be improved by utilising the PICO framework to look like this:
Compiling a list of search terms
Let’s look at two of the concepts from the research question: 1) allergic rhinitis, and 2) acupuncture.
When you start compiling a list of possible search terms you need to think of your own keywords, as well as the thesaurus (i.e. subject) terms used by each of the databases you will be searching.
The following table shows some keywords and thesaurus terms for allergic rhinitis and acupuncture. The thesaurus terms are MeSH (Medical Subject Headings) as used by the PubMed database. Thesaurus terms for other databases would be added to the list.
seven star needle
transcutaneous nerve stimulation
transcutaneous electrical nerve stimulation
(Medical Subject Headings)
rhinitis, allergic, seasonal
rhinitis, allergic, perennial
transcutaneous electric nerve stimulation
Combining search terms
To combine the different search terms the boolean operators of OR and AND need to be used.
Use the boolean operator OR to combine keywords related to a single concept. This broadens your search, increasing the number of results. This means that each search term listed for allergic rhinitis would be combined with an OR, and similarly for acupuncture.
Use the boolean operator AND to combine keywords related to different concepts. This narrows your search, decreasing the number of results. The search results for allergic rhinitis would be combined with an AND with the search results for acupuncture.
The search query
Our search query using the PubMed database and the listed keywords and MeSH terms for allergic rhinitis, and similarly for acupuncture, would look like the following:
The search result set for each would then be combined with the boolean operator AND to give the final search result number for the respective database. The search query would look like the following:
|problem AND intervention|
The library guide Starting your literature review has a page that addresses planning your search. It covers identifying the main aspects/concepts of your topic, compiling a list of search terms, utilising different search techniques, and the search query.