Classification-Index

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Classification 2025 Summer Edition

Worldwide source of medical classification resources

Class Index

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Openbite See Open Bite

Operant Conditioning See Conditioning, Operant

Operating Room Nursing WY 162

Education

WY 18 - WY 18.5

Operating Room Technicians WO 21.5

Operating Rooms WX 200

Architectural planning and construction

WX 140

Operation Desert Shield See Gulf War

Operation Desert Storm See Gulf War

Operation Iraqi Freedom See Iraq War, 2003-2011

Operation New Dawn See Iraq War, 2003-2011

Operational Research See Operations Research

Operations Research

General

T 57.6

Medical

W 20.55.O6

Special topics (form number 20 or 20.5 in any NLM schedule where applicable)

See also Information Theory

Operative Dentistry See Dentistry, Operative

Operative Procedures See Surgical Procedures, Operative

Operative Surgical Procedure See Surgical Procedures, Operative

Operative Surgical Procedures See Surgical Procedures, Operative

Operidine EPJ-I See Meperidine

Ophidia See Snakes

Ophiophagus hannah Venom See Elapid Venoms

Ophthalmia See Endophthalmitis

Ophthalmia Neonatorum WW 212

Ophthalmia, Sympathetic WW 525

Ophthalmic Artery WG 595.O7

Ophthalmic Assistants WW 21.5

Ophthalmic Dispensers See Opticians

Ophthalmic Dispensing See Opticians

Ophthalmic Nerve WL 330

Ophthalmic Solution See Ophthalmic Solutions

Ophthalmic Solutions WW 166

Ophthalmodynamometry WW 270

Ophthalmologic Surgical Procedure See Ophthalmologic Surgical Procedures

Ophthalmologic Surgical Procedures

General

WW 168

Infant or child

WW 168

Of a particular disorder, with the disorder