This video demonstrates how to use the MeSH, or Medical Subject Headings, database to create
a targeted PubMed search. From the PubMed homepage, in the More Resources section, I’ll click the link to the MeSH database. MeSH is the controlled vocabulary used for indexing PubMed citations.
Let’s say I want to find articles about problems associated with giving flu vaccines
to individuals with egg allergies. I’ll first search for “flu vaccine,” which
returns the MeSH term, Influenza Vaccines. The page displays a definition and additional
information about the term. In the MeSH database, terms are arranged hierarchically
by subject categories with more specific terms arranged beneath broader terms. You’ll notice
that Influenza Vaccines is listed under Viral Vaccines, which is under Vaccines. I’ll
click Vaccines to display the variety of terms available under this concept.
Let me take a two sentence aside, here, to mention how MeSH terms help your searches.
During the indexing process, the most specific MeSH terms are applied to a journal article.
Then during your PubMed search, MeSH terms recognized in the query are automatically
mapped to the most specific terms and those are included in your search.
Okay, I’ll click back to Influenza Vaccines and continue with my search. These Subheadings
may be used to narrow the search. Since I’m interested in the negative effects of the
flu vaccine, I’ll click the subheading “adverse effects,” and then click the button “Add
to search builder.” I want to further limit to articles on egg
allergies, so I’ll search MeSH as I did with flu vaccines to find the appropriate
MeSH term. I’ll enter “egg allergy” in the search box at the top of the page.
The database displays the MeSH term Egg Hypersensitivity, which I’ll add to my PubMed search by clicking
the “Add to search builder” button. I’m now ready to search PubMed, so I’ll click
“Search PubMed”. This search retrieves a relatively small number
of targeted citations. You’ll notice that all of these citations are tagged with the
text “[PubMed – indexed for MEDLINE].” This indicates that the citation has been
indexed with MeSH terms; but, please keep in mind that not all PubMed citations are
slated to be MeSH indexed, and it may take several weeks for a new citation to be indexed,
so using MeSH terms will limit your results to a subset of PubMed citations.
To see all the MeSH terms used to index an article, click on an article title and then
click on the MeSH Terms label. Each MeSH term includes a menu that can be used search the
term in PubMed or MeSH. Back on the MeSH homepage, you can read more
about using MeSH by following the Help link, and send questions by using the link, Write
to the Help Desk.