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

General Principles

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Library of Congress Classification vs. NLM Classification

  • Some LCC numbers or range of numbers appear in the NLM Classification index
  • Although LCC numbers are verified against the LCC schedules periodically, the pertinent LCC schedules must be consulted since the numbers may change over time
  • In some cases, a term is indexed to numbers in both the NLM and the LC classification schedules, depending on emphasis
  • If medical aspects predominate, classify the work in the NLM schedule
  • If social, religious, or other aspects predominate, classify in the LCC schedule
  • In case of doubt, prefer the NLM schedule
    • Example:

       

      Screen capture of Abortion Induced example.

       

    • A general work on social problems related to induced abortion is classed in the LCC schedule general works number for abortion, HQ 767-767.52. A work on how to perform an abortion is classed in the NLM schedule number for abortion, WQ 440

Human Medicine vs. Animal Medicine

  • If the emphasis is on human medicine, classify with the medical aspect in the NLM schedule
    • Example:
      • A work discussing cancer research using laboratory animals in order to learn what causes cancer in humans, is classified in QZ with works on the etiology of cancer in humans 
  • For materials that discuss both humans and animals, prefer classification with the human
  • When an animal is discussed in connection with research, classify in QY under the specific number for the animal, if available, or the general number for Animals, Laboratory, if no specific number is available
  • Care and breeding of laboratory animals also goes in QY
  • When animal diseases, anatomy, and physiology, or the care and breeding of domestic animals are discussed, choose an appropriate number from the LCC schedules
  • When the focus is on the laboratory animal rather than the disease, class with the laboratory animal


Last Reviewed: April 16, 2021