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Fact Sheet
Bibliographic Services Division (BSD)

The Bibliographic Services Division, a part of Library Operations, provides access to the biomedical journal literature and other data sources produced by the National Library of Medicine (NLM). It does this primarily through the production of MEDLINE®, a database of bibliographic citations and abstracts of the biomedical and life sciences journals. The MEDLINE database is accessed through the PubMed® database system, and is also licensed to researchers and commercial database providers. Statistical data are available at: // BSD also provides support for other NLM systems such as the Unified Medical Language System (UMLS), the Value Set Authority Center (VSAC), and

The Division has two sections: Index Section and MEDLARS Management Section. In addition, the staff of the Office of the Chief, BSD, is responsible for supporting the Associate Director for Library Operations and the NLM Literature Selection Technical Review Committee (LSTRC) in the review of journals for inclusion in MEDLINE. The Division works with publishers of journals recommended by LSTRC to receive acceptable electronic citation and abstract data for inclusion in MEDLINE.

Index Section

The Index Section, which produces MEDLINE data, is the largest component of BSD. The Section reviews bibliographic citations for each article published in journals covered by MEDLINE, and performs subject analysis by which concepts discussed in each article are assigned descriptors from the Medical Subject Headings (MeSH®) controlled vocabulary. Additional metadata entries about article are also assigned.

The Index Section performs gene indexing by creating annotated links between MEDLINE citations and records for genes and proteins in the Entrez Gene database. The Section's chemical specialists add new supplementary chemical concepts to the MeSH headings each year. In addition, Indexers supply suggestions for new MeSH terms as they encounter new concepts in the literature. For details, please see also Frequently Asked Questions about Indexing.

Article citations are supplied electronically by publishers, and subject to review for completeness and accuracy. Completed citations may be linked by the Index Section staff to related citations. The Index Section also edits MEDLINE citation entries based on published errata, or from reports from publishers, editors, or users. For details, see the NLM fact sheet Errata, Retraction, Partial Retraction, Corrected and Republished Articles, Duplicate Publication, Comment, Update, Patient Summary and Republished (Reprinted) Article Policy for MEDLINE.

MEDLARS Management Section (MMS)

MMS is responsible for facilitating and improving access to bibliographic data and publications, and to supporting the NLM’s activities in terminology development and management. The primary focus is database development, data management, system testing and quality assurance to foster expanded access of health information to health professionals and the general public. MMS staff collaborates with the National Center for Biomedical Information (NCBI), Lister Hill Center (LHC), and Office of Computer and Communications Systems (OCCS) staff on development and refinement of Web page design, new features and testing of new versions of PubMed, the UMLS and its related systems, the Value Set Authority Center (VSAC), and other NLM systems. There is ongoing testing for data quality and investigation of reports from the public of questionable data.

MMS is in charge of developing national training programs, online training and user documentation for PubMed, UMLS, VSAC, LinkOut for Libraries, and; manages NLM data licensing and distribution programs for NLM and UMLS data; incorporates user feedback into product development; performs software and system testing for UMLS, MEDLINE, and PubMed systems; and answers specialized customer inquiries. MMS staff assists with the LinkOut program, being the primary support for the LinkOut for Libraries component. MMS leads the conversion of older citations from pre-1966 printed indexes and the mapping of the old keywords assigned to those citations to current MeSH, both of which increase the amount of data available to users.

MMS is also responsible for the production of the NLM Technical Bulletin, an online bulletin that serves as the official channel for distributing news and information about NLM systems.

For general information on NLM services, contact:

National Library of Medicine
Customer Service
8600 Rockville Pike
Bethesda, MD 20894
Telephone: 1-888-FINDNLM (1-888-346-3656)
email: //
NLM Customer Support

A complete list of NLM Fact Sheets is available at:
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Phone: (301) 496-6308
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