The National Library of Medicine (NLM) is currently involved in MEDLINE year-end processing (YEP) activities. These include changing the Medical Subject Headings (MeSH) main headings and subheadings as well as Supplementary Concept Records that standardize names and associated numbers for chemicals, protocols, diseases and organisms that are not main headings. The MeSH edits include maintaining existing MEDLINE citations to conform with the 2019 version of MeSH, and other global changes.
For details about the impact on searching from November 28 to mid-December, visit Annual MEDLINE/PubMed Year-End Processing (YEP): Impact on Searching During Fall 2018.
In addition, an alternate link to provide access to 2019 MeSH is available from the top navigation bar on the MeSH Browser homepage. The default year in the MeSH Browser remains 2018 MeSH for now. Sometime in November or December, the default year will change to 2019 MeSH and the alternate link to 2018 MeSH.