Health Sciences Descriptors
The trilingual and structured
vocabulary DeCS - Health Sciences Descriptors - was created by BIREME to serve as a
unique language in indexing articles from scientific journals, books,
congress proceedings, technical reports, and other types of materials, as well as for searching and retrieving
subjects from scientific literature from information sources available on
the Virtual Health Library (VHL)
such as LILACS, MEDLINE,
It was developed from the MeSH - Medical Subject Headings of the U.S. National Library of Medicine (NLM) with the purpose of permitting the
use of common terminology for searching in three languages, providing a
consistent and unique environment for the retrieval of information regardless
of the language.
DeCS is part of the LILACS
Methodology and is an integrating component of the Virtual Health
DeCS participates in the unified terminology development
project, UMLS - Unified Medical Language
System of the NLM,
with the responsibility of contributing with the terms in Portuguese and
BIREME also developed terminology in specific
areas such as Public Health, Homeopathy, Science
and Health, and Health Surveillance in addition to the original
The concepts that characterize the DeCS vocabulary are
organized in a tree structure allowing a search on broader or narrower terms or
on all terms from the same tree within the hierarchical structure.
DeCS is a dynamic vocabulary totaling 31,865
descriptors, of which 27,232 come from MeSH, and
4,633 are exclusively DeCS. There is an addition
of 2,084 hierarchic codes from DeCS categories in
1,516 MeSH descriptors. The following are the DeCS categories and their total number of descriptors:
Health Surveillance (827); Homeopathy (1,945), Public Health (3,492); and
Science and Health (218). The sum is greater than the total number of
descriptors, since a descriptor may occur more than once in the hierarchy.
By being dynamic, it records a permanent process of change including the
development of new areas of terminology.
With the creation of the national, institutional
and thematic VHLs, search strategies were made available in the various
topics in order to facilitate the retrieval of the existing literature.
The updating annually performed in MeSH and the
modifications also carried out in the other DeCS
categories, demand the revision and update of the search strategies on the
thematic areas of each BVS, especially the ones including hierarchical
codes. Therefore, it is advised that the team responsible for their
creation also make sure that these strategies can be revised annually
before implementing them. Read text on how to revise strategies used
in searching thematic areas of a VHL.
Date of last update: March, 2014