The Northwestern University Libraries produces the Library of Congress, Northwestern University subset. It is part of the Library of Congress Subject Headings (LCSH)/Medical Subject Headings (MeSH) mapping project.
The LCSH and MeSH mapping project maps corresponding headings from both systems. The mapping data is entered in the 750 and 788 linking entry fields in LCSH and MeSH.
The subset includes the LCSH terms that map to MeSH.
The Metathesaurus only includes data from the 010, 1XX (Heading Information) and 750 fields (Heading Linking Entry).