What’s new in 2008 DeCS

This article highlights the additions and changes in the DeCS vocabulary in 2008.

Overview of Vocabulary Development and Changes

· 456 MeSH descriptors and 6 DeCS descriptors were added; the ten subcategories receiving the greatest additions were the enzymes and coenzymes (88), amino acids, peptides and proteins (85), social sciences (22), cardiovascular diseases (19), neoplasms (18), cells (14), nervous system diseases (11), organic compounds (11), chemical actions and uses (10) and equipment and supplies (9);

· 288 MeSH descriptors were replaced with more up-to-date terminology

· 46 MeSH descriptors and 1 DeCS descriptor were eliminated

· 177 MeSH synonyms were added

· 39 DeCS descriptors had their English version updated

· 449 DeCS descriptors had their Spanish version updated

· 418 DeCS descriptors had their Portuguese version updated

Totals by Type of Terminology

Annual Growth	2007	2008	difference	variation
Total MeSH descriptors (MH+PT)	24357	24767	410	1,7%
Total MeSH subheadings (MQ)	83	83	0	0,0%
Total DeCS descriptors (DH+DQ)	4727	4723	-4	0,0%
Total DeCS synonyms per language average	30043	31175	1132	3,8%
Total Concepts	29167	29573	406	1,4%

MH= MeSH Headings; PT=Publication Types; MQ=MeSH Subheadings; DH=DeCS Headings; DQ=DeCS Subheadings

New Descriptors by Tree Category

Tree Category	Number of descriptors
A – Anatomy	38
B – Organisms	16
C – Diseases	73
D – Chemicals and Drugs	217
E – Analytical, Diagnostic and Therapeutic Techniques and Equipment	30
F – Psychiatry and Psychology	2
G – Biological Sciences	33
H – Natural Sciences	12
HP – Homeopathy	0
I – Anthropology, Education, Sociology and Social Phenomena	27
J – Technology, Industry, Agriculture	6
K – Humanities	1
L – Information Science	1
M – Named Groups	5
N – Health Care	34
SH – Science and Health	0
SP – Public Health	6
V – Publication Characteristics	3
VS – Health Surveillance	0
Z – Geographicals	1

The total is more than 462 because some descriptors occur in more than one category.

DeCS 2008 edition is available for online searching through the DeCS Search or directly from the BIREME homepage.

A complete list of new and changed vocabulary is available at these links:

New MeSH and DeCS Descriptors with Scope Notes - 2008

New MeSH and DeCS Descriptors by category - 2008

Replaced MeSH and DeCS Descriptors - 2008

Deleted MeSH and DeCS Descriptors - 2008

DeCS tree number changes - 2008

MeSH tree number changes - 2008

Leukemia – Lymphoma Changes

The official nomenclature in this field has gone through many changes over the years and the MeSH tree structure in this area had not been revised, in toto, for a long time. The main authority source used in this revision was the International Classification of Diseases for Oncology (ICD-O), 3d edition, supplemented by recent papers and texts^[1]. Members of some working groups who are advising on the upcoming 4th edition were also consulted.

Many of the leukemia terms have undergone name changes as immunophenotypic and molecular biological techniques have made diagnosis more precise. For instance the old descriptor LEUKEMIA, MYELOID, CHRONIC is now called LEUKEMIA, MYELOGENOUS, CHRONIC, BCR-ABL POSITIVE. The old descriptor LEUKEMIA, MYELOID, PHILADELPHIA-NEGATIVE is now LEUKEMIA, MYELOID, CHRONIC, ATYPICAL, BCR-ABL NEGATIVE.

The old classification system for lymphomas was discarded for a simpler model. Many old names are now obsolete, though some have been retained as entry terms. This includes morphological descriptions of cell types like "small cleaved-cell" or "large-cell" or "undifferentiated" and grading such as "high grade" or "diffuse." These phrases were contained in old descriptors which now are subsumed under NON-HODGKINS LYMPHOMA or FOLLICULAR LYMPHOMA.

In some cases the distinctions between leukemias and lymphomas are now considered artificial, and so the nomenclature contains new descriptors such as PRECURSOR CELL LYMPHOBLASTIC LEUKEMIA-LYMPHOMA.

Finally, the terms indented under HISTIOCYTIC DISORDERS, MALIGNANT have undergone significant changes.

Government Agencies

Forty eight descriptors were created for those Institutes within the U.S. National Institutes of Health (NIH) which previously were not represented. The new array, which also includes a few new non-NIH agencies, is below. It can also be viewed in DeCS or in MeSH at: http://www.nlm.nih.gov/mesh/trees2008/I01.html (scroll down to Government).

Note: The National Institute of Neurological Disorders and Stroke was inadvertently omitted and will be added next year.

Publication Types

To make clearer the distinction between descriptors that describe the subject matter of a bibliographic item and the descriptors that characterize the format of the item, the entire set of Publication Types was reviewed. For those where intellectual pairs were found, the subject matter MeSH descriptor was modified to include the words "as Topic." All publication type descriptors were revised to remove the rubric [Publication Type].

Thus for 2008, here are a few examples:

as subject descriptor	as format characterization
Abbreviations as Topic	Abbreviations
Almanacs as Topic	Almanacs
Metanalysis as Topic	Metanalysis
Randomized Controlled Trial as Topic	Randomized Controlled Trial

Other additions

Besides the annual changes related to the vocabulary, the following implementations were made in the search system:

Sensitization of scope and indexing notes permitting navigation through the existing terms that are also descriptors or synonyms in DeCS, as NLM’s MeSH Browser.

Example:

Integration now also of the DeCS concept to VHL information sources, ordering the results by similarity/relevance and by number of references, which may be adjusted according to the user’s objectives.

Example:

Creation of alphabetical rulers for each language

Example:

Example of an alphabetical list of DeCS terms: terms beginning with the letter S

From: Schulman J. What's New for 2008 MeSH®. NLM Tech Bull. 2007 Nov-Dec;(359):e11. Available in Internet: http://www.nlm.nih.gov/pubs/techbull/nd07/nd07_mesh.html

DeCS Unit/BIREME/PAHO/WHO

Additional information: MEDLINE® data changes — 2008

^[1] Fritz, A [and others], editors. International classification of diseases for oncology (ICD O). 3rd ed. Geneva: World Health Organization; 2000. 240 p.

Date of last update: June 19, 2008