W General Medicine. Health Professions
WA Public Health
WB Practice of Medicine
WC Communicable Diseases
WD Disorders of Systemic, Metabolic or Environmental Origin, etc.
WE Musculoskeletal System
WF Respiratory System
WG Cardiovascular System
WH Hemic and Lymphatic Systems
WI Digestive System
WJ Urogenital System
WK Endocrine System
WL Nervous System
WM Psychiatry
WN Radiology. Diagnostic Imaging
WO Surgery
WP Gynecology
WQ Obstetrics
WR Dermatology
WS Pediatrics
WT Geriatrics. Chronic Disease
WU Dentistry. Oral Surgery
WV Otolaryngology
WW Ophthalmology
WX Hospitals and Other Health Facilities
WY Nursing
WZ History of Medicine. Medical Miscellany