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The Library uses the NLM classification system for cataloging our books. A few helpful tips for when you are reading a call number:
All letters are kept in alphabetical order and alphabetized as if they were a word.
Nothing comes before something. Ex: A1 comes before AA1, C45 comes before C45a. Read each line as follows:
First line is read as if it were a word.
Second line is read as a whole number.
Third line begins with letters that are read as if they were a word, followed by numbers that are read as a decimal point, reading the numbers place by place. Ex.: C745 comes before C8. Letters that follow numbers are read as if they were a word.
There may be a fourth line comprised of letters and numbers. Follow the same rules as the third line.
Subsequent line is the year of publication.
Subsequent line may list volume numbers.
Need an overview of the classification so you can browse for a specific content area?
Take a look at the NLM Classification poster. OUTLINE OF NLM CLASSIFICATION
QS Human Anatomy
QU Biochemistry. Cell Biology and Genetics
QW Microbiology and Immunology
QY Clinical Pathology
Medicine and Related Subjects:
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
WN Radiology. Diagnostic Imaging
WT Geriatrics. Chronic Disease
WU Dentistry. Oral Surgery
WX Hospitals and Other Health Facilities
WZ History of Medicine. Medical Miscellany
19th Century Schedule