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Medical Subject Headings® - Overview

The Medical Subject Headings comprise NLM's controlled vocabulary used for indexing articles, for cataloging books and other holdings, and for searching MeSH-indexed databases, including PubMed.

MeSH terminology provides a consistent way to retrieve information that may use different terminology for the same concepts. MeSH organizes its descriptors in a hierarchical structure so that broad searches will find articles indexed more narrowly. This structure also provides an effective way for searchers to browse MeSH in order to find appropriate descriptors.

The MeSH vocabulary is continually updated by subject specialists in various areas. Each year hundreds of new concepts are added and thousands of modifications are made.

For more detailed information concerning MeSH see the Introduction to MeSH