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DB / Metadata Management Program (MMP): Fundamentals of the NLM® Classification

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Updates to NLM Classification


  • The online NLM Classification is twice a year by the NLM Classification Editorial Team

  • The Class Team’s activities include:
    • Systematic review of selected schedules
    • Additions/changes to the index based on new or replaced MeSH headings
    • Verification of selected LC class numbers used in the index
    • Resolution of classification problems raised by NLM catalogers and customers.

  • Outside subject experts/medical librarians may be consulted before major changes to the schedules are made

  • Classification problems or suggestions may be submitted to the NLM Support Center https://support.nlm.nih.gov/


Last Reviewed: April 16, 2021