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TSD / Cataloging and Metadata Management: Using Medical Subject Headings (MeSH®) in Cataloging

Module 2— Descriptor Records


MeSH Heading

  • MeSH Heading
    • The preferred term for a descriptor
    • Often a broader concept that includes narrower sub-concepts

Unique Identifier

  • Unique ID
    • Seven-character alpha-numeric string uniquely identifying a descriptor
    • Always starts with the letter “D”

Tree Number

  • Alpha-numeric string referring to the location of the descriptor within a hierarchy. Each heading in the tree carries a tree number that begins with the letter from the top of the tree followed by numbers. The longer the number, the more specific the concept. A MeSH descriptor record may contain more than one tree number.
  • Used for drilling down in the MeSH vocabulary
    • Example
      • C02.839.040 is one of the tree numbers for Acquired Immunodeficiency Syndrome

Screen capture of MeSH Browser showing the tree number for Acquired Immunodeficiency Syndrome.

Last Reviewed: July 28, 2017