PubMed Tutorial from The Levy Library: MeSH Database vs. Search Builder
Why Use the MeSH Database?
MeSH terms can be selected for searching in the MeSH database and from suggestions and the index in the advanced Search Builder. So, why use the MeSH Database?
1. Use the MeSH Database to look up MeSH vocabulary in the MeSH Thesaurus.
The Search Builder will suggest MeSH terms, but it will not do a full search of the MeSH vocabulary to find all terms or the best terms for your search. The MeSH database will look for matches to your search terms in all the fields of all the MeSH database records. Then you can choose the best terms from the results.
2. Use the MeSH Database to "coordinate" (attach) MeSH headings and subheadings.
You can choose to search terms in the MeSH Term AND Subheading fields from the Search Builder, but these terms are not attached, or "coordinated". The MeSH Database allows you to coordinate MeSH Terms and subheadings.
You use the Search Builder to construct a search for acquired immunodeficiency syndrome[MeSH Terms]) AND drug therapy[MeSH Subheading] and retrieve nearly 12,000 results, many on the drug treatment of other diseases that are complications of AIDS.
A coordinated search built in the MeSH Database, "Acquired immunodeficiency syndrome/drug therapy"[Mesh], retrieves about 8,000 on-target results.
3. Use the MeSH Database to examine the MeSH hierarchy (MeSH Tree) and adjust your search.
The MeSH tree hierarchy is especially helpful if you are not familiar with your topic - it allows you to view the term in a variety of contexts. You can also make sure you are searching at the right level in the tree, and if not, select a broader or narrower term.
You can also choose to search without including lower terms in the hierarchy.
You are interested in the drug therapy of chronic asthma, a much studied topic. You decide to do a MeSH search. You see that the narrower concepts under the MeSH term of Asthma include descriptors that are not relevant to your query, e.g., "Status Asthmaticus", which is an acute, life threatening emergency.
For better results, select "Do not include MeSH terms found below this term in the MeSH hierarchy" from the MeSH Database checkbox.