MeSH 2021

The National Library of Medicine (NLM) adopted the 2021 MeSH vocabulary for cataloging on December 7, 2020.

Implications for LocatorPlus and the NLM Catalog

Accordingly, MeSH subject headings in LocatorPlus were changed to reflect the 2021 MeSH vocabulary and appear in that form as of December 7, 2020.

It is anticipated that the NLM Catalog database and translation tables will be updated to reflect 2021 MeSH by mid-December 2020. Until then, there will be a brief hiatus in the addition of new and edited bibliographic records to the NLM Catalog.

Implications for the NLM Classification

The winter version to be published in late January 2021 will encompass changes to the NLM Classification resulting from new and changed MeSH terms for 2021 as well as additional minor updates to the index. The main index terms will continue to link to 2020 MeSH until the Winter 2021 edition is published in January.

The NLM Classification number appears in many terms in the MeSH Browser and is supplied by CaMMS (Cataloging and Metadata Management Section) when the MeSH term points to a single classification number. These class numbers are current as of the Winter 2020 edition of the NLM Classification. They will be updated with the publication of the 2021 Winter edition in January 2021.

MeSH 2021 Changes in NLM Bibliographic Records and Cataloging Policy

Generally, vocabulary changes in NLM bibliographic records for books, serials, and other materials were implemented as they were applied for citations in MEDLINE. For additional information, see MEDLINE Data Changes—2021.  

There were no Publication Types added or changed for MeSH 2021.

There were no new MeSH descriptors marked as CATALOG: Do not use.