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NLM Classification 2023 Summer Edition Now Available

NLM Classification 2023 Summer Edition Now Available. NLM Tech Bull. 2023 Sep-Oct;(452):e1.

September 05, 2023 [posted]
October 31, 2023 [Editor's note added]

[Editor's note: This article was originally published under "In Brief" on the so23 issue cover.]

The National Library of Medicine (NLM) Classification has been updated. NLM is committed to regularly updating and revising the NLM Classification based on advancements in science and current events. Each year NLM selects portions of the classification schedules for systematic review and revision.

Scope of the 2023 Summer Edition

The major focus of the 2023 summer edition was the systematic review of the following schedules: WR Dermatology and WW Ophthalmology. In addition to the systematic reviews of the WR and WW schedules, other minor additions and changes were made.

Summary Statistics for the 2023 Summer Edition

1 schedule header modified
22 class numbers added
2 range headers added
72 class number captions or notes modified
7 range headers modified
9 class numbers canceled
1 range headers deleted
55 index main headings added
130 index entries modified
44 index headings deleted

Systematic Reviews for the 2023 Summer Edition

Highlights from the WR Dermatology

7 NEW WR CLASS NUMBERS

New Class Number	Caption
WR 103	Radiation effects on the skin. Sunburn
WR 104	Touch
WR 110	Skin care
WR 147	Acneiform eruptions
WR 149	Rosacea
WR 155	Keratosis (General or not elsewhere classified)
WR 380	Tick infestations

3 CANCELED WR CLASS NUMBERS

Deleted Class Number	Former Caption	New Instructions for Classification
WR 267	[Pigmentation disorders] Of metabolic origin	Classify pigmentation disorders of metabolic origin in WR 265.
WR 330	Tinea capitis	Class tinea capitis infections in WR 310.
WR 390	Skin appendages	None

22 MODIFED WR CLASS NUMBERS
5 MODIFED CLASS NUMBERS IN OTHER SCHEDULES RELATED TO WR SYSTEMATIC REVIEW

Highlights from the WW Ophthalmology

9 NEW WW CLASS NUMBERS

New Class Number	Caption
WW 21.7	Optometry and opticianry as a profession
WW 104	Ocular vision
WW 140.5	Vision disorders (General or not elsewhere classified)
WW 225	Corneal diseases
WW 258	Crystalline lens. Lens diseases
WW 272	Retinal diseases (General or not elsewhere classified)
WW 273	Retinal degeneration
WW 274	Retinal detachment
WW 285	Ocular hypertension

6 CANCELED WW CLASS NUMBERS

Deleted Class Number	Former Caption	New Instructions for Classification
WW 352	Principles. Calculations. Tables	None
WW 480	Medical aspects of reading problems associated with poor vision	None
WW 704	General works. Office management	Classify general works on optometry and on office management at WW 350.
WW 721	Optometry and opticianry as professions. Ethics. Peer review	Classify works on optometry and opticianry as a profession in WW 21.7.
WW 722	[Optometry] Directories (Table G)	Classify optometry directories in WW 22.
WW 722.1	[Optometry directories] General coverage (Not Table-G)	Classify optometry directories in WW 22.

31 MODIFED WW CLASS NUMBERS
4 MODIFED CLASS NUMBER IN OTHER SCHEDULES RELATED TO WW SYSTEMATIC REVIEW

Additional Changes

Several classification issues were investigated and resolved.

Problem	Resolution
Where to class social aspects of Autism Spectrum Disorder?	Added sub-index (SI) to Autism Spectrum Disorder: Social aspects HV 1570.2- HV 1570.25
Need guidance on classification of general works on chronic disease hospitals and sanatoriums	Added main number to Chronic Disease Hospital: QZ 23-QZ 24. Modified caption at QZ 23-24 to add Chronic Disease Hospital.
Need guidance on classification of cytological techniques in cell biology versus cytological techniques in clinical pathology	Added instructional notes to QU 25 and QY 95 about the appropriate classification of cytological techniques in cell biology (QU 25) and cytological techniques in clinical pathology (QY 95). Changed sub-index (SI) under Cytological Techniques from Cytology to Cell biology.
Classification of Forensic Anthropology is out of sync with definition in MeSH Scope note	Changed class for Forensic Anthropology from W 750 (Other forensic sciences) to W 800 (Examination of dead bodies. Duties of coroners). Added Forensic Anthropology to W 800 caption at the beginning. Fixed note at W 750.
Need guidance on where to classify Health Services for Persons with Disabilities which is not in the index.	Created new number WA 370 for Health Services for Persons with Disabilities with Table G. Added Health Services for Persons with Disabilities to the index and classed new number WA 370. Adjusted SI for Disabled Persons.
The definition of Neglected Diseases has expanded per WHO. The classification needs to reflect that.	Reclassed Neglected Diseases from QZ 140 (Pathologic processes (General)) to new number WC 685 following Tropical Diseases.
Where to class works on Nobel Prizes for medicine?	Created a new number WZ 400 Awards and prizes. Added Awards and Prizes to the index. Modified index entry for Nobel Prizes.
Where to class the MeSH 2022 term Prolonged Grief Disorder which is not in the index?	Broadened WM 172.5 caption from stress disorders to Trauma and stressor related disorders. Added Trauma and Stressor Related Disorders and Prolonged Grief Disorder to the index classed at WM 172.5. Added new number WM 172.6 for Adjustment Disorders.
Where to class general works on how racism affects health?	Add Sub-index to Racism: Health impact (General) WA 30
Should specific traditional medicine practitioners be classed with the practice?	The index record for Traditional Medicine Practitioners was modified to provide guidance on classification of specific practitioners
The caption Physical therapy at WM 405 is misleading in the Psychiatry schedule	Changed caption at WM 405 from Physical therapy to Psychiatric somatic therapies. Added Psychiatric Somatic Therapies to index.

Next Edition

The 2024 winter edition will be published in late January 2024. It will encompass the additions and changes from the 2024 MeSH (Medical Subject Headings) vocabulary as evaluated for inclusion in the Classification index. All main index headings will be linked to the 2024 vocabulary in the MeSH Browser at that time.

The NLM Classification number appears in many terms in the MeSH browser and is supplied by the Cataloging and Metadata Management Section (CaMMS) when the MeSH term points to a single classification number. These class numbers are current as of the Winter 2023 edition of the NLM Classification. They will be updated with the publication of the 2024 winter edition in January 2024.

To learn more about the NLM Classification see the NLM Policy on Classification.