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United States National Library of Medicine National Institutes of Health

Fact Sheet
Bibliographic Services Division, (BSD)


The Bibliographic Services Division provides access to biomedical literature. It does this primarily through:



The Division is composed of two Sections: Index and MEDLARS Management. In addition, the staff of the Office of the Chief, BSD, is responsible for:

Index Section

The Index Section, which produces MEDLINE data, is the largest component of BSD. The section creates bibliographic citations for each article added to MEDLINE, and performs subject analysis by which every concept that is discussed in each indexable article is assigned one or more descriptors from the Medical Subject Headings (MeSH®) controlled vocabulary which contains over 19,000 terms. More than eleven million articles from approximately 4,600 of the world's preeminent biomedical journals have been indexed for MEDLINE since its inception in 1966, and approximately 500,000 articles are indexed for the database yearly.

Indexers are biomedical subject specialists with degrees in science, and are also experts in one or more foreign languages since the section analyzes journals written in approximately 30 languages. Foreign language specialists from the section assist the Literature Selection Technical Review Committee (LSTRC) in reviewing non-English journals for possible inclusion in Index Medicus and MEDLINE.

Most subject indexing is performed by contractors, some is produced in-house, and some by international MEDLARS Centers. Indexers examine complete articles, whether in print or electronic format; they do not rely on abstracts to convey the contents of the full article. See also Frequently Asked Questions about Indexing on the BSD Web Home Page.

Members of the Index Section in-house train new indexers and review the work produced outside of NLM for accuracy and consistency. In addition, the section's chemical specialists add about 7,000 new supplementary concepts (mostly chemical) to the MeSH headings each year, and supply the majority of suggestions for new MeSH terms because they continually encounter new concepts in the literature. Members of the Index Section assist in the definition, treeing, and annotation of new MeSH concepts.

Article citations may be supplied electronically by publishers, subject to review by the Index Section's bibliographic specialists for completeness and accuracy; or produced by optical character recognition-assisted technology; or keyed from the journal issues by contractors. Completed citations may be linked by the Index Section staff to related citations. See the NLM fact sheet Errata, Retraction, Duplicate Publication, and Comment Policy. The Index Section also corrects MEDLINE errors detected by users.

MEDLARS Management Section (MMS)

MMS is responsible for facilitating and improving access to bibliographic data and publications. Their primary focus is database development, management, testing and quality assurance to foster expanded access of health information to health professionals and the general public. MMS staff was responsible for much of the effort in converting data from the mainframe computer environment to more modern systems such as PubMed®, and works with the National Center for Biomedical Information (NCBI) and Lister Hill Center (LHC) staff on development and refinement of search screens, new features, and testing of new versions of PubMed and the NLM Gateway. There is ongoing testing for data quality and investigation of reports from the public of questionable data. MMS also has coordination and liaison responsibilities with collaborating data producers in the areas of bioethics and space life sciences. Most MMS staff are librarians or technical information specialists.

MMS also develops national training programs and user documentation for PubMed, the NLM Gateway, and UMLS (Unified Medical Language System); prepares various printed bibliographies such as Index Medicus, manages NLM's data licensing and distribution programs for NLM data and UMLS; incorporates user feedback into product development; and answers specialized customer inquiries.


A complete list of NLM Fact Sheets is available at:
(alphabetical list) http://www.nlm.nih.gov/pubs/factsheets/factsheets.html
(subject list): http://www.nlm.nih.gov/pubs/factsheets/factsubj.html

Or write to:

FACT SHEETS
Office of Communications and Public Liaison
National Library of Medicine
8600 Rockville Pike
Bethesda, Maryland 20894

Phone: (301) 496-6308
Fax: (301) 496-4450
email: publicinfo@nlm.nih.gov

Last updated: 12 March 2003
First published: 12 March 2003
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