National Library of Medicine (NLM) Records (Additions and Changes to Authority Records)

The National Library of Medicine (NLM) catalogs medical titles in the CIP program. Headings and usage in the NLM bibliographic and authority files are taken into account in preparing new AACR2 headings and also in certain instances when LC has already formulated an AACR2 heading, but the NLM files would support a different heading. For headings used by NLM, the NLM heading has precedence over the LC heading when:

1. the LC heading has not yet been coded for AACR2, and the NLM heading has already been established as AACR2.

2. the LC heading has been coded as AACR2-compatible (Descriptive cataloging rules fixed field 008/10 = d) and NLM has established the heading as "pure" AACR2 (Descriptive cataloging rules fixed field 008/10 = c).

3. both libraries have headings already coded as "pure" AACR2 and NLM has a greater number of bibliographic records in support of its heading than LC has in support of its heading. (If the number is equal, the better heading is chosen, basing the decision on judgment.)

National Library of Medicine Examples

See also:

Section II - Additons and Changes to Authority Records