Medical Subject Headings (
MeSH) is a comprehensive
controlled vocabularyControlled vocabularies provide a way to organize knowledge for subsequent retrieval. They are used in subject indexing schemes, subject headings, thesauri, taxonomies and other form of knowledge organization systems...
for the purpose of
indexingAn index is a list of words or phrases and associated pointers to where useful material relating to that heading can be found in a document...
journal articles and books in the life sciences; it can also serve as a
thesaurusA thesaurus is a reference work that lists words grouped together according to similarity of meaning , in contrast to a dictionary, which contains definitions and pronunciations...
that facilitates searching. Created and updated by the
United States National Library of MedicineThe United States National Library of Medicine , operated by the United States federal government, is the world's largest medical library. Located in Bethesda, Maryland, the NLM is a division of the National Institutes of Health...
(NLM), it is used by the
MEDLINEMEDLINE is a bibliographic database of life sciences and biomedical information. It includes bibliographic information for articles from academic journals covering medicine, nursing, pharmacy, dentistry, veterinary medicine, and health care...
/
PubMedPubMed is a free database accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintains the database as part of the Entrez information retrieval system...
article database and by NLM's catalog of book holdings.
MeSH can be browsed and downloaded free of charge on the Internet through
PubMedPubMed is a free database accessing primarily the MEDLINE database of references and abstracts on life sciences and biomedical topics. The United States National Library of Medicine at the National Institutes of Health maintains the database as part of the Entrez information retrieval system...
. The yearly printed version was discontinued in 2007 and MeSH is now available online only. Originally in English, MeSH has been translated into numerous other languages and allows retrieval of documents from different languages.
Structure of MeSH
The 2009 version of MeSH contains a total of 25,186
subject headings, also known as
descriptors. Most of these are accompanied by a short description or definition, links to related descriptors, and a list of synonyms or very similar terms (known as
entry terms). Because of these synonym lists, MeSH can also be viewed as a
thesaurusA thesaurus is a reference work that lists words grouped together according to similarity of meaning , in contrast to a dictionary, which contains definitions and pronunciations...
.
Descriptor hierarchy
The
descriptors or
subject headings are arranged in a
hierarchyA hierarchy is an arrangement of items in which the items are represented as being "above," "below," or "at the same level as" one another...
. A given descriptor may appear at several places in the hierarchical tree. The tree locations carry systematic labels known as
tree numbers, and consequently one descriptor can carry several tree numbers. For example, the descriptor "Digestive System Neoplasms" has the tree numbers C06.301 and C04.588.274; C stands for Diseases, C06 for Digestive System Diseases and C06.301 for Digestive System Neoplasms; C04 for Neoplasms, C04.588 for Neoplasms By Site, and C04.588.274 also for Digestive System Neoplasms. The tree numbers of a given descriptor are subject to change as MeSH is updated. Every descriptor also carries a unique alphanumerical ID that will not change.
Descriptions
Most subject headings come with a short description or definition. See the
MeSH description for diabetes type 2 as an example. The explanatory text is written by the MeSH team based on their standard sources if not otherwise stated. References are mostly encyclopaedias and standard textbooks of the subject areas. References for specific statements in the descriptions are not given, instead readers are referred to the
bibliography.
Qualifiers
In addition to the descriptor hierarchy, MeSH contains a small number of standard
qualifiers (also known as
subheadings), which can be added to descriptors to narrow down the topic. For example, "Measles" is a descriptor and "epidemiology" is a qualifier; "Measles/epidemiology" describes the subheading of epidemiological articles about Measles. The "epidemiology" qualifier can be added to all other disease descriptors. Not all descriptor/qualifier combinations are allowed since some of them may be meaningless. In all there are 83 different qualifiers.
Supplements
In addition to the descriptors, MeSH also contains some 139,000
Supplementary Concept Records. These do not belong to the controlled vocabulary as such and are not used for indexing MEDLINE articles; instead they enlarge the thesaurus and contain links to the closest fitting descriptor to be used in a MEDLINE search. Many of these records describe chemical substances.
Use in Medline/PubMed
In MEDLINE/PubMed, every journal article is indexed with some 10-15 headings and subheadings, with some of them designated as
major and marked with an asterisk. When performing a MEDLINE search via PubMed, entry terms are automatically translated into (= 'mapped to) the corresponding descriptors with a good degree of reliability; it is recommended to check the
Details tab in PubMed to see how a search formulation was 'translated'. By default a search will include all the descriptors that are located below the given one in the hierarchy.
Categories
The top-level categories in the MeSH descriptor hierarchy are:
- Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
[A]
- Organism
In biology, an organism is any contiguous living system . In at least some form, all organisms are capable of response to stimuli, reproduction, growth and development, and maintenance of homoeostasis as a stable whole.An organism may either be unicellular or, as in the case of humans, comprise...
s [B]
- Diseases [C]
- Chemicals
In chemistry, a chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e. without breaking chemical bonds. They can be solids, liquids or gases.Chemical substances are...
and Drugs [D]
- Analytical, Diagnostic
Medical diagnosis refers both to the process of attempting to determine or identify a possible disease or disorder , and to the opinion reached by this process...
and Therapeutic Techniques and Equipment [E]
- Psychiatry
Psychiatry is the medical specialty devoted to the study and treatment of mental disorders. These mental disorders include various affective, behavioural, cognitive and perceptual abnormalities...
and PsychologyPsychology is the study of the mind and behavior. Its immediate goal is to understand individuals and groups by both establishing general principles and researching specific cases. For many, the ultimate goal of psychology is to benefit society...
[F]
- Biological Sciences [G]
- Physical Sciences [H]
- Anthropology
Anthropology is the study of humanity. It has origins in the humanities, the natural sciences, and the social sciences. The term "anthropology" is from the Greek anthrōpos , "man", understood to mean mankind or humanity, and -logia , "discourse" or "study", and was first used in 1501 by German...
, EducationEducation in its broadest, general sense is the means through which the aims and habits of a group of people lives on from one generation to the next. Generally, it occurs through any experience that has a formative effect on the way one thinks, feels, or acts...
, SociologySociology is the study of society. It is a social science—a term with which it is sometimes synonymous—which uses various methods of empirical investigation and critical analysis to develop a body of knowledge about human social activity...
and Social Phenomena [I]
- Technology and Food
Food is any substance consumed to provide nutritional support for the body. It is usually of plant or animal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals...
and Beverages [J]
- Humanities
The humanities are academic disciplines that study the human condition, using methods that are primarily analytical, critical, or speculative, as distinguished from the mainly empirical approaches of the natural sciences....
[K]
- Information Science
-Introduction:Information science is an interdisciplinary science primarily concerned with the analysis, collection, classification, manipulation, storage, retrieval and dissemination of information...
[L]
- Persons [M]
- Health Care
Health care is the diagnosis, treatment, and prevention of disease, illness, injury, and other physical and mental impairments in humans. Health care is delivered by practitioners in medicine, chiropractic, dentistry, nursing, pharmacy, allied health, and other care providers...
[N]
- Publication
To publish is to make content available to the public. While specific use of the term may vary among countries, it is usually applied to text, images, or other audio-visual content on any medium, including paper or electronic publishing forms such as websites, e-books, Compact Discs and MP3s...
Characteristics [V]
- Geographic Locations [Z]
For the full hierarchy, see
List of MeSH codes.
See also
- GoPubMed
GoPubMed is a knowledge-based search engine for biomedical texts. TheGene Ontology and Medical Subject Headings serve as "Table of contents" in order to structure the millions of articles of the MEDLINE database. The search engine allows its users to find relevant search results significantly...
, searching Medline with MeSH as "table of content"
- Medical classification
Medical classification, or medical coding, is the process of transforming descriptions of medical diagnoses and procedures into universal medical code numbers...
- Medical literature retrieval
Medical literature retrieval or medical document retrieval is an activity that uses professional methods for medical research papers retrieval, report and other data to improve medicine research and practice.-Professional medical search engine:*Pubmed...
External links