Peggy Tahir
Peggy is Copyright & Research Librarian at the UCSF Library. Contact Peggy for help with copyright, database searching, reference managers, and evidence-based medicine.

MeSH Changes for 2018

Medical Subject Headings

The MeSH thesaurus is used to index the articles that appear in PubMed. Each year, new terms are added, and older terms are retired or transitioned to newer terms. Here are the latest changes; they may affect how you decide to structure your PubMed searches.

This year, there were 474 new descriptors added, 106 terms replaced with more up to date terminology, 7 descriptors deleted, and 1 subheading deleted. Here is a link to the changed and deleted terms.

There are also expanded and updated terminology areas in these fields: Isotopes and radioisotopes, smoking, sugars, and virus terminology (which includes a new Supplementary Concept Record (SCR) class for Organisms).

The MeSH qualifier (subheading) deleted was /contraindications. To cover the concept, three new MeSH terms were added:


  • Contraindications, Drug
  • Contraindications, Procedure

There are now three new publication types in PubMed. Two are for clinical trials: Adaptive Clinical Trial and Equivalence Trial. An equivalence trial aims to show when a new treatment is no better and no worse than the standard treatment. The MeSH terms added along with these new publication types are Adaptive Clinical Trials as Topic and Equivalence Trials as Topic. Also related is Proof of Concept (falling as a child in the MeSH tree hierarchy under Research), which pertains to investigations pertaining to the development of prototypes or models. The third new publication type is Expression of Concern. This is a notification about the integrity of a published article. The detailed description is on the linked page.