What's new for DeCS 2020

This article highlights changes to DeCS in 2020.

Totals by type of terminology

DeCS language 2019 2020 variation 19/20
amount %
Descriptors English 33889 34041 152 0,45%
Spanish (America) 33889 34041 152 0,45%
Spanish (Spain) 33889 34041 152 0,45%
Portuguese 33889 34041 152 0,45%
Termos Alternativos English 214448 218803 4355 2,03%
Spanish (America) 58101 60670 2569 4,42%
Spanish (Spain) 48913 51380 2467 5,04%
Portuguese 63548 67078 3530 5,55%
Qualifiers English 77 77 0 0,00%
Spanish (America) 77 77 0 0,00%
Spanish (Spain) 77 77 0 0,00%
Portuguese 77 77 0 0,00%
Total 520659 534403 13744 2,64%

Changes for 2020

Subcategories receiving the greatest number of new descriptors:

Subcat code Subcategory name Amount of descriptors
Organic Chemicals
Amino Acids, Peptides, and Proteins
Investigative Techniques
Enzymes and Coenzymes
Pathological Conditions, Signs and Symptoms
Environment and Public Healt
Technology, Industry, and Agriculture
Eye Diseases
Nervous System Diseases
Information Science

New descriptors per category

DeCS/MeSH tree category
Amount of descriptors
A - Anatomy
B - Organisms
C - Diseases
D - Chemicals and Drugs
E - Analytical, Diagnostic and Therapeutic Techniques and Equipment
F - Psychiatry and Psychology
G - Phenomena and Processes
H - Disciplines and Occupations
HP - Homeopathy
I - Anthropology, Education, Sociology and Social Phenomena
J - Technology, Industry, Agriculture
K - Humanities
L - Information Science
M - Named Groups
N - Health Care
SH - Science and Health
SP - Public Health
V - Publication Characteristics
VS - Health Surveillance
Z - Geographicals
The total is greater than the number of new descriptors because some of them occur in more than one category.

2020 DeCS 2020 is available for online searching through DeCS Search or directly from VHL Regional Portal.

Helpful Links

Please consult the DeCS 2020 edition or the online Introduction to MeSH 2020 for more details.
The complete lists of the changes to the vocabulary are available on the links below:

Vocabulary changes

New descriptors

Replaced descriptors

Deleted descriptors

DeCS e MeSH tree number changes

MeSH 2020 highlights:

MeSH is available in RDF linked data format.

MeSH 2020 is available for download in XML, ASCII and MeSH / MARC.

Changes to MeSH/DeCS Headings

(A) MeSH Publication Types

1) One new publication type is available for MEDLINE indexing in 2020:

Randomized Controlled Trial, Veterinary

Indexing policy: Use for the original report of the conduct or results of a specific randomized veterinary clinical trial in which animal participants are randomly assigned to receive one or more interventions.

Use the MeSH headings Clinical Trials, Veterinary as Topic and Randomization for the general design, methodology, economics, etc. of randomized veterinary clinical trials.

2) Four preferred terms are changed for publication types that are used for MEDLINE Indexing:

• Evaluation Studies -> Evaluation Study

• Government Document -> Government Publication

• Validation Studies -> Validation Study

• Webcasts -> Webcast

One MeSH heading is changed to a publication type. This publication type is used for Cataloging only. A new "as Topic" MeSH heading was not created:

• Biobibliography as Topic -> Biobibliography

3) MeSH "as Topic" Headings:

Fictional Works as Topic

Observational Studies, Veterinary as Topic

Single-Case Studies as Topic

4) A total of ten preferred terms are changed for "as Topic" MeSH headings:

• Autobiography as Topic -> Autobiographies as Topic

• Bibliography as Topic -> Bibliographies as Topic

• Biography as Topic -> Biographies as Topic

• Duplicate Publication as Topic -> Duplicate Publications as Topic

Four additional preferred terms for "as Topic" MeSH headings are changed. Note that their corresponding publication types are used for Cataloging only:

• Diary as Topic -> Diaries as Topic

• Exhibits as Topic -> Exhibitions as Topic

• Programmed Instruction as Topic -> Programmed Instructions as Topic

• Study Guide as Topic -> Study Guides as Topic

Two preferred terms for "as Topic" MeSH headings are changed to remove "as Topic" from the string. Note that these headings are not changed to publication types.

• Abstracting and Indexing as Topic -> Abstracting and Indexing

• Advertising as Topic -> Advertising

(B) MeSH Tree Changes

For a list of MeSH/DeCS tree hierarchical changes, see "DeCS and MeSH tree number changes"

Alterações significativas na categoria C (Doenças) incluem:

1) MeSH Categories C01, C02, and C03 are consolidated

• Consolidated the tree nodes for Bacterial Infections and Mycoses [C01], Virus Diseases [C02], Parasitic Diseases [C03] into a single category Infections (C01).

• The preferred term for the MeSH heading Infection is changed to Infections and a new entry term of Infections and Infestations is added.

• The MeSH heading Infections is the new name for category C01.

• The headings Bacterial Infections and Mycoses, Virus Diseases and Parasitic Diseases are repositioned under category Infections C01.

• This tree reconfiguration will make retrieval for Infections inclusive of all terms under Infections for 2020.

• Two new MeSH headings are added as children to category Infections (C01).

o Vaccine-Preventable Diseases

o Vector Borne Diseases

2) MeSH Category Cell Physiological Phenomena (G04) is updated

• One new MeSH heading is added as a child to category Cell Death (G04.146) and six new headings are added as grandchildren:

o Regulated Cell Death

Autophagic Cell Death


Immunogenic Cell Death

Mitochondrial Transmembrane Permeability-Driven Necrosis



• Five new MeSH headings are added as children to category Autophagy (G04.011)

o Autophagic Cell Death

Note: This new MeSH heading is in two tree positions as a child to Autophagy and Regulated Cell Death

o Chaperone-Mediated Autophagy

o Macroautophagy

o Microautophagy

o Mitophagy

Note: In 2020, the preferred term for Mitochondrial Degradation is replaced by Mitophagy. This MeSH heading is in two tree positions as a child to Autophagy and Mitochondrial Turnover [G04.599].

Autophagy is removed from categories Cell Death [G04.146] and Phagocytosis [G04.417.350] and repositioned as a child to Cell Physiological Phenomena [G04].

Necrosis and its children are removed from Cell Physiological Phenomena [G04.146.638] and retain their positions in Pathological Conditions, Signs and Symptoms [C23.550.717].

(C) MeSH Special Projects

Several special projects resulted in the following new 2020 MeSH headings:

1) Food related headings:

Animal Proteins, Dietary

Artificially Sweetened Beverages

Edible Insects

Pork Meat


Sugar-Sweetened Beverages

2) Health Services headings:

Military Health Services

School Mental Health Services

Veterans Health Services

3) Person headings:

Atomic Bomb Survivors

Indigenous Peoples

Intersex Persons


4) Psychiatry and Psychology related headings:

Avoidant Restrictive Food Intake Disorder

Body Dissatisfaction

Body Integrity Identity Disorder


Emotional Regulation

Food Fussiness

Psychological Distress

Suicide, Completed

5) Toxicity headings:



6) 11 new MeSH headings on non-human primate terminology:

Alouatta caraya

Ateles geoffroyi


Cebus capucinus



Macaca arctoides

Macaca fuscata



Sapajus apella

(D) Two MeSH concepts merged into one

1) Cascara merged into Rhamnus and is not retained as entry term. Cascara Sagrada and Sacred Bark are retained as entry terms to Rhamnus. Casanthranol is retained as entry term to Emodin

2) Coniferophyta merged into Tracheophyta. Coniferophyta is retained as an entry term. Punicaceae merged into Lythraceae. Punicaceae is retained as an entry term. Taxodiaceae merged into Cupressaceae. Taxodiaceae is retained as an entry term.

(E) Do not confuse

1) Case Reports with Single-Case Studies as Topic, which are trials that consider an individual patient as the sole unit of observation in a study investigating the efficacy or side-effects of different interventions to determine the optimal intervention for an individual patient using objective data-driven criteria. Also note that Single-Case Studies as Topic is used for indexing articles on the general design, methodology, etc. for Single Case Trials.

2) Food Fussiness with Avoidant Restrictive Food Intake Disorder, which is an eating or feeding disturbance that manifests as persistent failure to meet nutritional needs leading to low weight, nutritional deficiency, dependence on supplemental feedings, and/or psychosocial functioning.

3) Rumination, Cognitive with Rumination Syndrome, which is a gastrointestinal disorder.

4) Stress, Psychological with Psychological Distress, which is an negative emotional state characterized by physical and/or emotional discomfort, pain, or anguish.

5) Undiagnosed Diseases with Missed Diagnosis, which is a failure to identify or diagnose a medical condition at the time a health professional is acquainted with the symptoms.

(F) Entry Combination Revisions



Phosphatidylinositol 3-Kinase/antagonists & inhibitors

Mandibular Nerve/injuries

Radio Waves/therapeutic use

Tumor Necrosis Factors/antagonists & inhibitors

Other News:

MEDLINE/PubMed Year-End Processing Activities

2020 MeSH Headings available in the MeSH browser

MEDLINE Data changes - 2020


Tybaert S. MEDLINE Data Changes - 2020. NLM Tech Bull. 2019 Nov-Dec;(431):e6a. Disponível na Internet: https://www.nlm.nih.gov/pubs/techbull/nd19/nd19_medline_data_changes_2020.html#mesh_changes

Adaptation: Health Terminologies and Classifications Section at BIREME/PAHO/WHO

Last update: April, 2020