May 20, 2022

Metadata: National Library of Medicine Formally Adopts 2015 MeSH (Medical Subject Headings), What’s New?

Two items from the National Library of Medicine’s Technical Bulletin.

1. What’s New For MeSH 2015

MeSH is the National Library of Medicine’s controlled vocabulary thesaurus which is updated annually. NLM uses the MeSH thesaurus to index articles from thousands of biomedical journals for the MEDLINE/PubMed database and for the cataloging of books, documents, and audiovisuals acquired by the Library.

Overview of Vocabulary Development and Changes for 2015 MeSH

  • 310 Descriptors added
  • 25 Descriptor terms replaced with more up-to-date terminology
  • 4 Descriptors deletes

Totals by Type of Terminology

  • 27,455 Descriptors
  • 83 Qualifiers
  • 224,925 Supplementary Concept Records


MeSH on Demand

MeSH on Demand, launched in May 2014, was developed to allow an easy way to identify relevant MeSH terms for text up to 10,000 characters (such as manuscript abstract, summary statement or description of a project) automatically. In the first full month of operation, 140,940 requests were made to MeSH on Demand. For additional information on MeSH on Demand see, MeSH on Demand Tool: An Easy Way to Identify Relevant MeSH Terms and MeSH on Demand Update: How to Find Citations Related to Your Text.

The remainder of the NLM Technical Bulletin article includes additional info and a number of useful links including an Introduction to MeSH-2015.

2. Cataloging News — 2015

The National Library of Medicine (NLM) adopted the 2015 MeSH vocabulary for cataloging on November 24, 2014.

Accordingly, MeSH subject headings in LocatorPlus were changed to reflect the 2015 MeSH vocabulary and appear in that form as of November 24, 2014.

The remainder of the article includes:

  • MeSH 2015 Changes in NLM Bibliographic Records and Cataloging Policy
  • MeSH Descriptors Not Used by Catalogers
  • Additional Database Changes
About Gary Price

Gary Price ( is a librarian, writer, consultant, and frequent conference speaker based in the Washington D.C. metro area. Before launching INFOdocket, Price and Shirl Kennedy were the founders and senior editors at ResourceShelf and DocuTicker for 10 years. From 2006-2009 he was Director of Online Information Services at, and is currently a contributing editor at Search Engine Land.