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Table of Contents: 2021 SEPTEMBER–OCTOBER No. 442

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NLM Classification 2021 Summer Edition Now Available

Willis, S. NLM Classification 2021 Summer Edition Now Available. NLM Tech Bull. 2021 Sep-Oct;(442):e1.

2021 September 21 [posted]

70th Anniversary of the NLM Classification

2021 marks the 70th anniversary of the NLM Classification. The first edition of the classification was published in 1951 as the U.S. Army Medical Library Classification. The name changed to the National Library of Medicine Classification with the second edition in 1956 to coincide with the library's name change. It is still recognized as a standard classification system for the arrangement of library materials in the field of medicine and related sciences used by health and medical libraries all over the world.

Systematic Reviews for the 2021 Summer Edition

The classification has been steadily built for over 70 years based on the scientific knowledge and current events of the time. A major restructuring of the entire classification is not feasible, but an annual systematic review of selected schedules is conducted.

The major focus of the 2021 summer edition was the systematic review of the following schedules: WU (Dentistry. Oral Surgery) and WV (Otolaryngology).

Statistics from the WU (Dentistry. Oral Surgery) Systematic Review

  • 23 WU class numbers added
New Class Number Caption
WU 29.1 General coverage (Not Table-G)
WU 29.3 Medical emergencies during dental care
WU 29.5 Dental infection control
WU 115 Oral hygiene
WU 120 Dental health education
WU 140.8 Mouth diseases
WU 192 Dental cements
WU 194 Dental porcelain
WU 195 Dental synthetic resins
WU 215 Tooth
WU 235 Tooth root. Root canal therapy
WU 240.5 Gingiva
WU 241 Periodontal diseases (General and not elsewhere classified)
WU 246 Tooth diseases (General or not elsewhere classified)
WU 247 Tooth injuries
WU 260 Tooth abnormalities
WU 272 Fluoridation. Fluoride treatment
WU 355 Dental restoration
WU 510 Dental prosthesis
WU 511 Crowns
WU 512 Dentures
WU 450 Public health dentistry
WU 626 Maxillofacial prosthesis
  • 7 WU numbers cancelled
Deleted Class Number Former Caption New Instructions for Classification
[WU 18.5] Education of dental assistants, hygienists, and technicians Classify works on education of dental auxiliaries in WU 18.
[WU 105] Dental emergencies (General) Classify works on medical emergencies during dental care in WU 29.3.
[WU 141.5] Specific diagnostic methods, A-Z Classify specific diagnostic methods in WU 141.
[WU 141.5.C3] Cephalometry Classify works on cephalometry used in dentistry in WU 141.
[WU 141.5.O2] Odontometry Classify works on odontometry in WU 215.
[WU 158] Oral and dental injuries (General) Classify works on tooth injuries in WU 247. Classify works on mouth injuries in WU 140.8.
[WU 170] Dental chemistry (General) Classify works on chemistry in LC's QD schedule.
  • 39 WU class number, captions, or notes were modified
  • 4 class numbers captions or notes modified in other schedules related to the WU systematic review
  • 13 index main headings added
  • 148 index entries modified
  • 44 index main headings deleted

Statistics from the WV (Otolaryngology) Systematic Review

  • 4 WV class numbers added
New Class Number Caption
WV 257 Vestibular diseases
WV 268 Vestibulocochlear physiological phenomena. Hearing
WV 480 Larynx
WV 485 Laryngeal diseases (General or not elsewhere classified)
  • 5 WV numbers cancelled
Deleted Class Number Former Caption New Instructions for Classification
[WV 280] Deaf-mutism Classify works on mutism associated with deafness in WV 270.
[WV 310] External nose Classify works on the nose in WV 300-WV 301.
[WV 400] General works Classify general works on the pharyngeal region in WV 410.
[WV 401] Anatomy. Physiology Classify works on anatomy and physiology of the pharynx in WV 410.
[WV 510] Inflammation Classify works on laryngitis in WV 485.
  • 27 WV class number captions or notes modified
  • 1 class number caption modified in another schedule related to the WV systematic review
  • 4 index main headings added
  • 72 index entries modified
  • 19 index main headings deleted

Next Edition

The 2022 winter edition will be published in late January 2022. It will encompass the additions and changes from the 2022 MeSH (Medical Subject Headings) vocabulary as evaluated for inclusion in the Classification index. All main index headings will be linked to the 2022 vocabulary in the MeSH Browser at that time.

By Sharon R. Willis
Cataloging and Metadata Management Section, Technical Services Division

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