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MEDLINE and MeSH Data Changes — 2023
MEDLINE and MeSH Data Changes — 2023. NLM Tech Bull. 2022 Nov-Dec;(449):e6.
December 12, 2022 [posted]
This article collects the notable data changes made to MEDLINE during the National Library of Medicine (NLM) annual maintenance known as Year-End Processing (YEP) for 2023:
- MeSH Vocabulary Updated for 2023
- MeSH Update Reports
- Special MeSH Projects
- Updated MeSH in MEDLINE Citations
MeSH Vocabulary Updated for 2023
The MeSH Browser points to the 2023 MeSH vocabulary with a link to the 2022 MeSH vocabulary. On December 2, the default switched to 2023 and the alternate link has been routed to 2022 MeSH. Searchers should consult the Browser to find MeSH headings of interest and their relationships to other headings. The Browser contains MeSH heading records that may include Scope Notes, Annotations, Entry Terms, History Notes, Allowable Qualifiers (Subheadings), Previous Indexing, and other information. It also includes Subheading records and Supplementary Concept Records (SCRs) for substances, diseases, and organisms that are not MeSH headings.
You can download 2023 MeSH from links on the NLM Data Distribution page for MeSH Data.
The PubMed MeSH database and translation tables will be updated to reflect 2023 MeSH by the middle of December when YEP activities are complete and the newly maintained MEDLINE data are available in PubMed.
MeSH Update Reports
Beginning with the release of 2023 MeSH, NLM now offers reports detailing the changes to the MeSH vocabulary. The nine MeSH 2023 Update reports detail the changes to MeSH terms that are performed during YEP. The MeSH 2023 Update allows users to view changes made to the MeSH vocabulary in various formats (CSV, PDF, HTML) as well as providing exportable reports (CSV, JSON, RDF, and XML). These include detailed reports regarding:
- Descriptors and SCRs Additions
- Preferred Term Updates
- Registry Number Updates
- Updates Made to All Fields
- Descriptor and SCR Replaces
- Entry Combination Updates
- Descriptor and SCR Splits
- Descriptor and SCR Deletes
- Merge Updates
Note: Typically, NLM does not retroactively re-index MEDLINE citations with new MeSH heading concepts. Therefore, searching PubMed for a new MeSH term tagged with [mh] or [majr] effectively limits retrieval to citations indexed after the term was introduced. Searchers may consult the MeSH database to see the previous indexing terms most likely used for a particular concept before the new MeSH heading was introduced. For terms without previous indexing information, consider the next broader term(s) in the MeSH hierarchy. For more searching guidance, see the on-demand class MeSH Changes and PubMed Searching.
Special MeSH Projects
Several special projects resulted in the following new 2023 MeSH headings:
New and Updated Population Group Headings
New and Updated Social Determinants of Health Headings
Updated MeSH in MEDLINE Citations
MEDLINE citations with updated MeSH are anticipated to be in PubMed by mid-December 2022. For instruction on how to adjust historical searches to changes in MeSH, see the on-demand class MeSH Changes and PubMed Searching.