United States National Library of Medicine National Institutes of Health

Number of Titles Currently Indexed for Index Medicus® and MEDLINE® on PubMed®

As of March 2009, 5,375 journals are currently indexed for MEDLINE. MEDLINE includes journals that are cited as Index Medicus as well as other non-Index Medicus journals. A breakdown is provided:

4,731	journals indexed as Index Medicus
644	additional, non-Index Medicus journals in the following areas:

	91	Dentistry (contribute to Citation Subset=D)
	25	AIDS/HIV (contribute to Citation Subset=X)
	19	Consumer Health (contribute to Citation Subset=K)
	193	Nursing (contribute to Citation Subset=N)
	116	Health care administration and delivery (contribute to Citation Subset=H)
	90	Health care technology indexed by NICHSR/NLM (contribute to Citation Subset=T)
	110	History of medicine core journals indexed fully by HMD/NLM (contribute to Citation Subset=Q or QIS)

Note: The above count does not include current journals selectively indexed by the HMD (History of Medicine Division, NLM), and, in the past NASA (National Aeronautics and Space Administration), and the KIE (Kennedy Institute of Ethics) sources. NASA ceased its collaboration with NLM in October 2005. KIE ceased indexing for NLM in January 2006. NICHSR stands for National Information Center on Health Services Research and Health Care Technology, NLM.

It may be helpful to know:

The journal list groupings above were created for NLM's in-house use, i.e., management of NLM’s indexing work flow.
A journal can belong to only one journal list.
These journal lists should not be confused with PubMed’s Subject Subsets. Subject Subsets may include citations from journals that are not part of the journal list for the same topic. For example, PubMed’s History of Medicine Subject Subset will not be limited to citations from the History of Medicine core journals
These journal lists should not be equated with PubMed’s Journal/Citation Subset data element (labeled as SB in the MEDLINE display format), although there is a connection between them. While a journal may belong to only one journal list, citations may be assigned multiple Citation Subset values. Every citation from a journal on a journal list will carry the Citation Subset value contributed by that journal list. Often when an Index Medicus journal fits into one of the special subject areas identified above, citations from that journal will have one Citation Subset value for Index Medicus and another Citation Subset value for the subject area. For example, British Dental Journal is an Index Medicus journal; citations from this journal have one Citation Subset value of IM for Index Medicus and a second Citation Subset value of D for Dentistry journal list. In addition, HMD and KIE, (and, in the past, NASA) may add their Citation Subset values to individual citations from any journal list title including Index Medicus journals. For example, this citation has three Citation Subset values of IM, D, and E for Ethics:

Adewumi A, Hector MP, King JM.
Children and informed consent: a study of children's perceptions and
involvement in consent to dental treatment.
Br Dent J. 2001 Sep 8;191(5):256-9.
PMID: 11575761 [PubMed - indexed for MEDLINE]
Abridged Index Medicus (AIM) is a list created over 20 years ago of about 120 core clinical English language journals. It corresponds to the "Core clinical journals" subset in PubMed's Limits.

For more information about journals see these resources:

The List of Journals Indexed for MEDLINE
The List of Serials Indexed for Online Users
LocatorPlus, NLM's online catalog
NLM Catalog, an Entrez database version of LocatorPlus bibliographic data; similar to PubMed in searching features
PubMed Journals Database, which also links to more information found in NLM Catalog which in turn links to LocatorPlus

Last reviewed: 26 March 2009
Last updated: 26 March 2009
First published: 31 October 2002
Metadata| Permanence level: Permanence Not Guaranteed