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Table of Contents: 2022 SEPTEMBER–OCTOBER No. 448

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NLM Classification 2022 Summer Edition Now Available

NLM Classification 2022 Summer Edition Now Available. NLM Tech Bull. 2022 Sep-Oct;(448):e1.

2022 September 07 [posted]

The NLM Classification was updated on August 31, 2022. 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.

The major focus of the 2022 summer edition was the systematic review of the following schedules: WF Respiratory System and WH Hemic and Lymphatic Systems. In addition to the systematic reviews of the WF and WH schedules, other minor additions and changes were made.

Summary Statistics for the 2022 Summer Edition

  • 35 class numbers added
  • 2 schedule range headers added
  • 78 class number captions or notes modified
  • 8 schedule range headers modified
  • 4 class numbers canceled
  • 1 schedule range headers deleted
  • 31 index main headings added
  • 199 index entries modified
  • 46 index headings deleted

Systematic Reviews for the 2022 Summer Edition

Highlights from the WF Respiratory Systematic Review

New Class Number Caption
WF 105 Respiration
WF 140.3 Respiration disorders
WF 140.5 Respiratory insufficiency
WF 140.7 Respiratory system infections
WF 141.5.L9 Lung volume measurements
WF 141.5.S8 Spirometry
WF 144 Apnea
WF 146 Artificial respiration
WF 148 Oxygen inhalation therapy
WF 235 Therapy
WF 302 Epidemiology (Table-G)
WF 302.1 [Epidemiology] General coverage (Not Table-G)
WF 304 Pathology
WF 306 Diagnosis
WF 555 Pediatric
WF 610 Anatomy. Histology. Embryology. Congenital abnormalities
WF 620 Physiology
WF 630 Lung diseases (General)
WF 972 Thoracic diseases
WU 511 Crowns

Deleted Class Number Former Caption New Instructions for Classification
WF 225 Mass chest X-ray Classify works on mass chest X-ray in WF 975
WF 290 Lymph node tuberculosis. Scrofula Classify works on lymph node tuberculosis in WH 700
WF 405 Tuberculosis in the workplace Classify works on occupational exposure to tuberculosis in WF 200-WF 390
WF 805 Functional disorders Classify works on functional disorders of diaphragm in WF 800


Highlights from the WH Hemic and Lymphatic Systems

New Class Number Caption
WH 173 Sickle cell anemia
WH 220 Lymphocytes
WH 260 Lymphoid leukemia
WH 265 Myeloid leukemia
WH 305 Hemostasis
WH 311 Fibrinolysis and associated blood proteins
WH 382 Bone marrow transplantation
WH 383 Hematopoietic stem cells. Hematopoietic stem cell transplantation
WH 470 Blood donation. Blood donors
WH 490 Hematologic neoplasms (General)
WH 720 Lymphatic diseases (General)

Additional Changes

Several classification issues were investigated and resolved.

Issue Resolution
Where to class non-human models as well as anatomic models of plants? Added Sub-Indexes (SIs) for animal and comparative anatomy of humans and animals to index record for Models, Anatomic. Also added SI for anatomic models of plants.
Where to class the new 2022 Medical Subject Headings (MeSH) Epidemiological Models which is not in the index. It trees under Models, Biological which is classed in QH but probably better classed in NLM classification. Epidemiological Models was added to index classed at WA 950. Adjusted header above WA 950 to add Epidemiologic Methods.
Where to class Models, Immunological? The parent term, Models, Biological points to QH 324.8. Added Models, Immunological to the index classed at QW 26.5.
Where to class Epigenomics: QU 460 with the broader term of Genomics or QU 475 based on the scope note? Created new number QU 476 Genetic Epigenesis. Epigenomics indented under QU 475. Reclassified pertinent child terms. Added note to QU 460: Classify epigenomics at QU 476.
Where to class Birth Setting? Its parent term, Parturition, is classed at WA 300. Its child term, Home Childbirth, is classed at WQ 155. Added Birth Setting to the index classed at WQ 155. Changed the caption at WQ 155 to broaden it from Home childbirth.
Where to class contact tracing in general? Currently the index only has guidance for contact tracing of sexually transmitted diseases. Added SI General WA 110 under Contact Tracing.
Domestic Violence is classed at WA 308 which is captioned Family Health. These are very different subjects. Family Violence (the MeSH Entry Term for Domestic Violence) was added to the caption at WA 308.
Where to class psychology of athletes. Should it be classed in WA 305 for mental health issues of special groups or with Sports Medicine in QT 260? Created new number for Sports psychology at QT 264. Added to index: Psychology, Sports QT 264.

Add SI Psychology QT 264 to index terms:

  • Athletes
  • Athletic Performance
The only class number for Speech Intelligibility is in WM. Speech Intelligibility is treed under Speech. Need a general number. Classed Speech Intelligibility only with Speech at WV 501.
Where to class collective biographies of traditional healers? Created new number for Collective Biography of Traditional Healers WZ 112.5.T7. Added SIs for this new number under all Traditional Medicine terms since there currently are no person terms in MeSH.
Where to class works on broad urogenital diseases that cover kidney, upper urinary tract, bladder, urethra, prostate, testis, penis, scrotum and adrenal gland. Currently the index for Urogenital Diseases points to WJ 700 which is general works on Male Genitalia. The range header above WJ 140 and the caption at WJ 140 were broadened from Urologic Diseases to Urogenital Diseases. Added note at WJ 140 to classify genital diseases at WJ 700.  Adjusted index record for Urogenital Diseases.
Should Vascular Diseases $x surgery be classed at WG 170 for Vascular surgical procedures or WG 505 for Vascular diseases (General or not elsewhere classified)? Added SI Surgery WG 170 to index record for Vascular Diseases.
Infanticide and Abortion, Criminal are both classed at W 867 but they are unrelated concepts. Infanticide trees only under Homicide. Abortion, Criminal is a sister term to Homicide, but does not tree under it. Removed Infanticide from W 867 caption.  Reclassified Infanticide with Homicide.
Review physical examination WB area to evaluate accuracy of classification and completeness. A mini-systematic review of the WB 205-WB 286 Physical examination area was conducted. Several WB captions were changed to reflect the technique (e.g., Blood pressure was changed to Blood pressure determination). Terms treeing in the MeSH tree Physical Examination [E01.370.600] were evaluated. Several index terms were added (e.g., Respiratory Rate).

Next Edition

The 2023 winter edition will be published in late January 2023. It will encompass the additions and changes from the 2023 MeSH vocabulary as evaluated for inclusion in the Classification index. All main index headings will be linked to the 2023 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 2022 edition of the NLM Classification. They will be updated with the publication of the 2023 Winter edition in January 2023.

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

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