MeSH (Medical Subject Headings) is a controlled vocabulary thesaurus that is used to index articles in Medline. A controlled vocabulary standardizes the nomenclature used to describe concepts that might occasionally be called by different names. (For example, if you enter "Rubeola" into a MeSH search, it will retrieve the preferred term "Measles" from the thesaurus.)
The MeSH system utlizes a hierarchical structure, so that related terms are grouped together, and searching may be done to varying levels of specificity. The heirarchy can be very useful if you need to find related terms, or see how various concepts are related to each other, or how they have changed over time.
The National Library of Medicine (NLM) provides an online MeSH database and supporting materials. But EBSCO's Medline incorporates MeSH into its interface, and by using the features shown in the first examples below you can use MeSH terms in your Medline searches. A bit further down the page are some screenshots from the NLM site in case you are interested in the nuts and bolts of MeSH straight from the NLM.
There are two ways to access the MeSH database through EBSCO's Medline interface. First, you can simply click on the "MeSH 2014" link at the top of the page, then enter a search term:
Or, you can check the "Suggest Subject Terms" box before entering your search terms:
Using either method, you'll get to a screen that looks like the shot below. You can check various terms to construct a search statement:
You build a search in the box to the right of the terms listing. When you're ready, click on "Search Database":
This is an example of MeSH's "tree," or heirarchical, structure:
When you click on a term, this is the information you receive. It can be very valuable to see the "Scope Note," or definition, as well as "See also" related terms, and a history of earlier nomenclature for the same concept: