Introduction to the Medical Subject Headings (MeSH^® Vocabulary)

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What is MeSH?

• Acronym for Medical Subject Headings
• The U.S. National Library of Medicine's controlled vocabulary (thesaurus)
• Gives uniformity and consistency to the indexing and cataloging of biomedical literature and is a distinctive feature of MEDLINE
• Similar to keywords on other systems
• Arranged in a hierarchical manner called the MeSH Tree Structures
• Updated annually

Who uses MeSH?

• Searchers of MEDLINE/PubMed, library catalogs, and other databases -- to assist with subject searching
• National Library of Medicine (NLM) indexers -- to describe subject content of journal articles for MEDLINE
• Catalogers -- to describe books and audiovisuals in the NLM and other medical library collections

MeSH Vocabulary includes four types of terms:

• Headings — over 24,000 headings represent concepts found in the biomedical literature

  Examples:

  Body Weight Kidney Dental Cavity Preparation Self Medication Radioactive Waste Brain Edema

• Subheadings — (also called qualifiers) attached to MeSH headings to describe a specific aspect of a concept

  Examples:

  adverse effects diagnosis metabolism therapy

  Note: See Subheading Hierarchical Groupings

• Supplementary Concept Records — over 172,000 terms in a separate chemical thesaurus [updated weekly]

  Examples:

  cordycepin valspodar tacrolimus binding protein 4

• Publication Characteristics (Publication Types) — describe the type of publication being indexed; i.e., what the item is, not what the article is about

  Examples:

  Letter Review Randomized Controlled Trial