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TSD / Cataloging and Metadata Management: Fundamentals of the NLM® Classification

Using the Online NLM® Classification

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Index Entries

All main headings are MeSH descriptors

Link to MeSH

  • Each main index heading is linked to the corresponding MeSH descriptor in the MeSH Browser via the "tree" icon Screen capture of MeSH Browser tree icon to the left of the main index term

  • Cross references do not have the MeSH link. Cross references may nor may not come from the MeSH vocabulary

  • The MeSH links generally point to the current MeSH year except between December and February when the next edition of the NLM Classification is being prepared. During this period, the MeSH links point to the previous year

Other Hyperlinks in the Index

  • From the Index headings to the appropriate classification numbers in the NLM Schedules. (LC classification numbers in the index are not hyperlinked)
  • From cross-references within the Index to the referred term

Sub-Indexes (SIs)

  • Facets of main index terms are entered in Sub-Indexes (SIs)
  • Sub-indexes (SI) associated with main index terms are collapsed. SIs are expanded by clicking on the plus sign. See also terms are hyperlinked to the related main index term.
  • Screen capture of Index SI collapsed example

  • Sub-indexes may have several indentation levels
  • Screen capture of Index SI collapsed example



Last Reviewed: April 16, 2021