Choose initial search terms, removing any words that are implied. For example, keywords patients with, decreased, increased, outcome should almost never be included in a search. Search each term separately then combine with AND.
Considering search terms for each PICO concept separately, improve your search by using one or more search techniques.
Search Technique | MeSH | Combine synonyms with OR | Filter for Age, Sex | Broader Term | Eliminate PICO element |
When to try it: |
A keyword search for a concept has other meanings or applications. A keyword search is returning results that are unrelated to your search concept. A MeSH term matches the search concept. |
Search is returning too few results. Multiple common ways to refer to a search concept No MeSH term for the search concept or the MeSH term does not exactly correlate to the search concept. |
Age, sex of the patient is important for relevance of articles Age, sex not implied by other search terms Search returns too many results |
Search is returning too few results A broader term is still clinically relevant |
Search is returning too few results One or more of your PICO elements is implied by others The term you eliminate isn't overly important to the relevance of your search results. |
A working set is the final search that returns the batch of articles from which to choose the best evidence. A working set is a reasonable attempt to capture the body of evidence related to the PICO.
The question domain helps you identify study designs appropriate to the question. Not sure which study types to look for? Use the domain and study type table to identify appropriate study types for each question domain.
Using article type filters in PubMed can help you systematically comb through your search results so you’re checking for the highest levels of evidence first.