PubMed Tutorial from The Levy Library: Practice Using MeSH
Scenario: You need to find articles on substances that act as insulin agonists.
To see the difference between searches, start with a basic search for insulin agonists. Remember to check that no Limits from previous searches are in effect.
You should retrieve over 5,000 citations. This is too many results to go through easily. More importantly, inspection shows that agonists of insulin are not the main focus of many of these citations. Some articles are about agonists of other substances, and mention insulin in a different context. We need to increase the search precision.
Step 1. Locate and select MeSH terms from the MeSH Database.
Open the drop-down menu near the PubMed query box and select MeSH (see screenshot, right). Then Search for Insulin. Note: although much of the interface looks the same, you are now searching the database of MeSH terms, NOT PubMed.
Your results will be a list of MeSH terms, with definitions. Select (click on) the one that looks most accurate, in this case, Insulin to see the MeSH record Full display format.
Step 2: Review the full MeSH record.
Definition: Immediately beneath the term, a definition will appear. Review the definition carefully to ensure hat you have chosen the correct term.
Subheadings: Beneathe the definitions will appear a list of the available subheading options.
Entry terms: the search terms that, when entered in the MeSH database, will "map" to the current MeSH term.
MeSH Tree: The MeSH tree hierarchy is especially helpful if you are not familiar with your topic, as it allows you to view the term in a variety of contexts. It can also sometimes help you discover better search terms. For example, upon reviewing the MeSH tree for the term Vaccine, you may discover that Bacterial Vaccines is also a MeSH term and that this term is a better fit for your search. As you move up the MeSH tree, the terms become broader and as you move down they become narrower. Note that our term appears under both "Peptides" and "Hormones".
Step 3: Use the full MeSH record options to further refine your search.
Check off the subheading for agonists. Remember: attaching subheadings to a MeSH term allows you to focus on a specific aspect of your topic. In this example, you will retrieve citations about agonists of insulin. You will NOT retrieve citations where "insulin" and "agonists" are both mentioned as separate concepts.
Next, scroll down below the subheadings and check off Restrict Search to Major Topic Headings Only so that your articles will have insulin agonists as a major focus.
Step 4: Launch the Search in PubMed.
Scroll back up to the top of the page and use the Add to search builder option to send your MeSH term and subheading to the PubMed Search Builder (find it on the upper right side of the MeSH full record screen — see example, right).
Note: The MeSH database query box is still available to search for more MeSH terms. You could continue to add MeSH terms to the search statement if you wished.
Finally, click the Search PubMed button to send the search to PubMed
Check out the Results. You should have retrieved about 20 citations in your results, down from over 5,000 retrieved at the beginning of this example. More importantly, you should have retrieved citations that directly address the topic of insulin agonists.