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

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Age Groups

  • NLM has two schedules devoted to specific age groups:
    • WS Pediatrics
    • WT Geriatrics
  • Some subjects have specific classification numbers for particular age groups
    • Example:

      Screen capture of Mental Disorders in the schedule.


WS Pediatrics

  • Classify in the WS schedule works on diseases of specific body systems in children (includes adolescents), as well as works on diseases limited to the newborn or premature infant unless there are specific instructions to the contrary
  • Classify works on specific diseases in children with the disease (e.g., pneumonia in infants in WC 202; schizophrenia in childhood in WM 203, etc.) unless there are specific instructions to the contrary
  • Classify works on anatomy or physiology of the child in QS or QT
  • Classify works on other topics dealing with children with the topic unless there are specific instructions to the contrary
  • Classify general works on pediatric and adolescent nursing in WY 159. Classify works on pediatric and adolescent nursing in special fields by type, e.g., on pediatric surgical nursing in WY 161
  • Some schedules other than WS have specific classification numbers devoted to children

Class NumberClass Caption
QZ 275 Pediatric oncology. Adolescent oncology (General)
WN 240 Pediatric diagnostic imaging
WO 440 Pediatric anesthesia
WO 925 Pediatric surgery
WU 113.6 [Oral health and hygiene] Works for and about children
WU 480 Pediatric dentistry. Dental care for children
WW 600 Pediatric ophthalmology and optometry

WT Geriatrics

  • Classify general works on the aged (65 and above) in the WT schedule
  • Classify works on specific diseases of the aged with the disease unless there are specific instructions to the contrary
  • Classify works on other topics dealing with the aged with the topic unless there are specific instructions to the contrary
  • Some schedules other than WT have specific classification numbers devoted to the aged

Class NumberClass Caption
WO 445 Geriatric anesthesia
WO 950 Geriatric surgery
WU 490 Geriatric dentistry. Dental care for the aged
WW 620 Geriatric ophthalmology and optometry


Last Reviewed: January 17, 2024