he NLM will cease publishing the Cumulated Index Medicus (CIM) with this 2000 edition (Volume 41). The publication of the monthly Index Medicus will not be affected.

The production of the first CIM in 1960 was a major achievement of the Index Mechanization Project that predated the MEDLARS system (MEDical Literature Analysis and Retrieval System). For decades, CIM enhanced access to the biomedical literature, but its utility has declined as online access to MEDLINE data has increased.

Several factors have influenced the timing of the decision to end publication of the CIM. Among these are declining subscriptions, easier access by libraries and individuals to the Internet where Index Medicus citations can be searched free in MEDLINE via PubMed, and the fact that there are a variety of other commercial products containing Index Medicus citations. In addition, there has been a decision by the Government Printing Office to permit electronic access in place of hard copy publications for the U.S. Depository Libraries program.

Citations in Index Medicus and MEDLINE constitute an invaluable resource, and NLM guarantees they will always be available. The method of access may change, as technology evolves, but the millions of references and abstracts will always be freely accessible to scientists, the health professionals, librarians, and the public.

2000 Cumulated Index Medicus: The End of an Era. NLM Tech Bull. 2001 Jul-Aug;(321):e3.