The National Library of Medicine (NLM) classification system is a library indexing system covering the fields of medicine and preclinical basic sciences. The NLM classification is patterned after the Library of Congress (LC) Classification system: alphabetical letters denote broad subject categories which are subdivided by numbers.
Preclinical sciences: QS - QZ
QS
Human Anatomy
QT
Physiology
QU
Biochemistry, Cell Biology and Genetics
QV
Pharmacology
QW
Microbiology and Immunology
QX
Parasitology
QY
Clinical Laboratory Pathology
QZ
Pathology
Medicine and related subjects: W - WZ
W
General Medicine. Health Professions
WA
Public Health
WB
Practice of Medicine
WC
Communicable Diseases
WD 100
Deficiency Diseases
WD 200
Metabolic Diseases
WD 300
Diseases of Allergy
WD 400
Animal Poisons
WD 500
Plant Poisons
WD 600
Disorders and Injuries of Environmental Origin
WD 700
Aviation and Space Medicine
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
Ophthalmology
WW
Ophthalmology
WX
Hospitals
WY
History of Medicine. Medical Miscellany
WZ
History of Medicine