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

Form Numbers

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Special Cases—History

  • In general, form number 11 is used for works dealing with the history of any aspect of a subject within a classification schedule
    • For example, WM 11 is used for both Psychiatry $x history and Psychotherapy $x history

Exceptions (noted in the schedule)

  • History of a drug is classed with the drug (not in QV 11)
  • W 11 and WB 11 are not used. Use instead the appropriate number in WZ schedule
    • In rare exceptions when there is no appropriate WZ number, the history of a topic is classed in the same number used for works on current practice in the W schedule
  • WB 900-962 are used for the history of complementary therapies
  • History of a single infectious disease is classed with the infectious disease (not in WC 11)
  • History of a society is classed in form number 1 in an NLM schedule where applicable
  • Histories of schools, laboratories, hospitals, institutes, etc. are classed in the appropriate form number for the type of entity
    • For example, history of a medical school is classed in W 19 while history of a laboratory is classed in QY 24


Last Reviewed: April 16, 2021