The National Library of Medicine (NLM) classification system is a
library indexing system covering the fields of
medicine
Medicine is the science and Praxis (process), practice of caring for patients, managing the Medical diagnosis, diagnosis, prognosis, Preventive medicine, prevention, therapy, treatment, Palliative care, palliation of their injury or disease, ...
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.
For example, ''QW 279'' would indicate a book on an aspect of
microbiology
Microbiology () is the branches of science, scientific study of microorganisms, those being of unicellular organism, unicellular (single-celled), multicellular organism, multicellular (consisting of complex cells), or non-cellular life, acellula ...
or
immunology
Immunology is a branch of biology and medicine that covers the study of Immune system, immune systems in all Organism, organisms.
Immunology charts, measures, and contextualizes the Physiology, physiological functioning of the immune system in ...
.
The one- or two-letter alphabetical codes in the NLM classification use a limited range of letters: only QS–QZ and W–WZ. This allows the NLM system to co-exist with the larger LC coding scheme as neither of these ranges are used in the LC system. There are, however, three pre-existing codes in the LC system which overlap with the NLM: ''Human Anatomy'' (QM), ''Microbiology'' (QR), and ''Medicine'' (R). To avoid further confusion, these three codes are not used in the NLM.
The headings for the individual ''schedules'' (letters or letter pairs) are given in brief form (e.g., QW - ''Microbiology and Immunology''; WG - ''Cardiovascular System'') and together they provide an outline of the subjects covered by the NLM classification. Headings are interpreted broadly and include the
physiological
Physiology (; ) is the science, scientific study of function (biology), functions and mechanism (biology), mechanisms in a life, living system. As a branches of science, subdiscipline of biology, physiology focuses on how organisms, organ syst ...
system, the specialties connected with them, the regions of the body chiefly concerned and subordinate related fields. The NLM system is
hierarchical
A hierarchy (from Greek: , from , 'president of sacred rites') is an arrangement of items (objects, names, values, categories, etc.) that are represented as being "above", "below", or "at the same level as" one another. Hierarchy is an importan ...
, and within each schedule, division by
organ
Organ and organs may refer to:
Biology
* Organ (biology), a group of tissues organized to serve a common function
* Organ system, a collection of organs that function together to carry out specific functions within the body.
Musical instruments
...
usually has priority. Each main schedule, as well as some sub-sections, begins with a group of form numbers ranging generally from 1–49 which classify materials by publication type, e.g.,
dictionaries
A dictionary is a listing of lexemes from the lexicon of one or more specific languages, often arranged Alphabetical order, alphabetically (or by Semitic root, consonantal root for Semitic languages or radical-and-stroke sorting, radical an ...
,
atlas
An atlas is a collection of maps; it is typically a bundle of world map, maps of Earth or of a continent or region of Earth. Advances in astronomy have also resulted in atlases of the celestial sphere or of other planets.
Atlases have traditio ...
es, laboratory manuals, etc.
The main schedules QS-QZ, W-WY, and WZ (excluding the range WZ 220–270) classify works published after 1913; the 19th century schedule is used for works published 1801–1913; and WZ 220-270 is used to provide century groupings for works published before 1801.
Overview of the NLM Classification categories
Preclinical Sciences
* QS Human Anatomy
* QT Physiology
* QU Biochemistry
* QV Pharmacology
* QW Microbiology & Immunology
* QX Parasitology
* QY Clinical Pathology
* QZ Pathology
Medicine and Related Subjects
* W 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 & Other Health Facilities
* WY Nursing
* WZ History of Medicine
* 19th Century Schedule
See also
*
Dewey Decimal Classification
The Dewey Decimal Classification (DDC) (pronounced ) colloquially known as the Dewey Decimal System, is a proprietary library classification system which allows new books to be added to a library in their appropriate location based on subject. ...
*
Colon classification
*
Library of Congress Classification
The Library of Congress Classification (LCC) is a system of library classification developed by the Library of Congress in the United States, which can be used for shelving books in a library. LCC is mainly used by large research and academic li ...
*
Universal Decimal Classification
The Universal Decimal Classification (UDC) is a bibliographic and library classification representing the systematic arrangement of all branches of human knowledge organized as a coherent system in which knowledge fields are related and inter-lin ...
References
Citations
Sources
*
{{Library classification systems
Medical classification
Knowledge representation
Library cataloging and classification
United States National Library of Medicine