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Finding the Appropriate Class Number

• After assigning the MeSH terms to a work, search the primary subject(s) in the index of the NLM Classification (Cf. Module 4—Descriptors: Selecting the Main Concept(s))

• Always check the main schedule for further instructions

• Read all annotations in the schedule (Note: Some general annotations appear at the beginning of the schedule)

• Take into account factors that may influence the classification (e.g., form, age group)

Specific Concepts

• In the NLM Classification index, some subjects may be indexed to a specific number. Note: these class numbers will also be visible in the MeSH browser, but the schedules should still be checked

  Example:

  


• Always refer to the main schedule to verify the number to be certain there are no annotations directing the cataloger to use another number in specific circumstances

General Concepts

• Some subjects may include a range of numbers. Refer to the section of the class schedule to which the primary subject is indexed and select the most appropriate number.
  

  Example:

  


• Refer to the section of the class schedule to which the primary subject is indexed and select the most appropriate number

• Select the class number annotated "General Works" if:
  • the subject is very general
  • the primary focus of the work includes several subjects within the schedule