Captured from https://www.ncbi.nlm.nih.gov/mesh Accessed: 08/24/2018
The MeSH database is the National Library of Medicine’s resource for medical vocabulary. It catalogs and describes the hierarchy of terminology used to describe biomedical information in MEDLINE. When you type your concept terms into MeSH, you’ll find a list of other medical synonyms and suggestions on how to search for these terms using PubMed.
It’s important to look for index terms because basic search terms only apply to words found in the database record for the paper, not the full text. Human indexers catalog all relevant terms- even those that aren’t in a study’s title or abstract.
Also, indexed terms may include multiple entry terms. For example, the concept for “heart attack” is indexed as myocardial infarction in MeSH. If you just search for “heart attack” you run the risk of missing papers that use the term myocardial infarction. Using the index terms helps you capture papers that use “heart attack” as well as those that use “myocardial infarction.”
To identify useful MeSH terms, you can find a record for a paper you know you plan to include in your review and look at the assigned MeSH terms to find ones that might be relevant.
MeSH terms describe how medical terminology is used in PubMed. If you are working in Embase, these terms are called “Emtree.” Likewise, CINAHL has its own specific vocabulary. Even though the names of these indexes are different, the way you use them is the same.
Once you’ve identified all of the words related to your research question, it’s time to string them together into sentences that form your search. We do that using something called boolean logic.