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MEDLINE Indexing Online Training Course

Category C - Diseases

Supplementary Concept Diseases

Although the MeSH vocabulary contains terms for a large number of diseases, there are many rare diseases which are not covered by existing MeSH terms. In order to enable accurate indexing, terms for these diseases were added to the MeSH vocabulary as Supplementary Concept Records (SCRs or Class 3 Descriptors). These SCR records map to existing MeSH headings. They appear in the MeSH Browser and in the IMS scroll-down list alphabetically along with MeSH headings. Indexing policy for these terms is the same as indexing policy for regular MeSH disease terms.

Supplementary Concept Record for Barakat syndrome
Screen capture of MeSH browser of the Supplementary Concept Diseases, Barakat syndrome.

Last Reviewed: December 5, 2017