National Library of Medicine classification
Encyclopedia
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. For example, QW 279 would indicate a book on an aspect of microbiology
or immunology
.
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
system, the specialties connected with them, the regions of the body chiefly concerned and subordinate related fields. The NLM system is hierarchical, and within each schedule, division by organ
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
, atlas
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.
Medicine and Related Subjects
Library classification
A library classification is a system of coding and organizing documents or library materials according to their subject and allocating a call number to that information resource...
covering the fields of medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
and preclinical basic sciences. The NLM classification is patterned after the Library of Congress (LC) Classification system
Library of Congress Classification
The Library of Congress Classification is a system of library classification developed by the Library of Congress. It is used by most research and academic libraries in the U.S. and several other countries; for example, Australia and Taiwan, R.O.C. It is not to be confused with the Library of...
: alphabetical letters
Alphabet
An alphabet is a standard set of letters—basic written symbols or graphemes—each of which represents a phoneme in a spoken language, either as it exists now or as it was in the past. There are other systems, such as logographies, in which each character represents a word, morpheme, or semantic...
denote broad subject categories which are subdivided by numbers. For example, QW 279 would indicate a book on an aspect of microbiology
Microbiology
Microbiology is the study of microorganisms, which are defined as any microscopic organism that comprises either a single cell , cell clusters or no cell at all . This includes eukaryotes, such as fungi and protists, and prokaryotes...
or immunology
Immunology
Immunology is a broad branch of biomedical science that covers the study of all aspects of the immune system in all organisms. It deals with the physiological functioning of the immune system in states of both health and diseases; malfunctions of the immune system in immunological disorders ; the...
.
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
Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...
system, the specialties connected with them, the regions of the body chiefly concerned and subordinate related fields. The NLM system is hierarchical, and within each schedule, division by organ
Organ (anatomy)
In biology, an organ is a collection of tissues joined in structural unit to serve a common function. Usually there is a main tissue and sporadic tissues . The main tissue is the one that is unique for the specific organ. For example, main tissue in the heart is the myocardium, while sporadic are...
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
Dictionary
A dictionary is a collection of words in one or more specific languages, often listed alphabetically, with usage information, definitions, etymologies, phonetics, pronunciations, and other information; or a book of words in one language with their equivalents in another, also known as a lexicon...
, atlas
Atlas
An atlas is a collection of maps; it is typically a map of Earth or a region of Earth, but there are atlases of the other planets in the Solar System. Atlases have traditionally been bound into book form, but today many atlases are in multimedia formats...
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 ClassificationDewey Decimal ClassificationDewey Decimal Classification, is a proprietary system of library classification developed by Melvil Dewey in 1876.It has been greatly modified and expanded through 23 major revisions, the most recent in 2011...
- Colon ClassificationColon classificationColon classification is a system of library classification developed by S. R. Ranganathan. It was the first ever faceted classification. The first edition was published in 1933. Since then six more editions have been published...
- Library of Congress ClassificationLibrary of Congress ClassificationThe Library of Congress Classification is a system of library classification developed by the Library of Congress. It is used by most research and academic libraries in the U.S. and several other countries; for example, Australia and Taiwan, R.O.C. It is not to be confused with the Library of...
- Universal Decimal ClassificationUniversal Decimal ClassificationThe Universal Decimal Classification is a system of library classification developed by the Belgian bibliographers Paul Otlet and Henri La Fontaine at the end of the 19th century. It is based on the Dewey Decimal Classification, but uses auxiliary signs to indicate various special aspects of a...