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MEDLINE Overview

MEDLINE is the National Library of Medicine’s (NLM) premier bibliographic database that contains more than 31 million references to journal articles in life sciences with a concentration on biomedicine.

MEDLINE is a primary component of PubMed, a literature database developed and maintained by the NLM National Center for Biotechnology Information (NCBI). MEDLINE is the online counterpart to the MEDical Literature Analysis and Retrieval System (MEDLARS) that originated in 1964 (see MEDLINE history). A distinctive feature of MEDLINE is that the records are indexed with NLM Medical Subject Headings (MeSH).

Selection process: The current procedure for adding new journals to MEDLINE is described on the page How to Include a Journal in MEDLINE.

Time coverage:
 MEDLINE includes literature published from 1966 to present, and selected coverage of literature prior to that period. For details about pre-1966 citations see OLDMEDLINE Data.

Source: Currently, citations from more than 5,200 worldwide journals in about 40 languages.

Updates: Citations are added to PubMed 7 days a week.

Subject coverage: In line with the Collection and Preservation Policy of the NLM, the subject scope of MEDLINE is biomedicine and health, broadly defined to encompass those areas of the life sciences, behavioral sciences, chemical sciences, and bioengineering needed by health professionals and others engaged in basic research and clinical care, public health, health policy development, or related educational activities. MEDLINE also covers life sciences vital to biomedical practitioners, researchers, and educators, including aspects of biology, environmental science, marine biology, plant and animal science as well as biophysics and chemistry.

The majority of the publications in MEDLINE are scholarly journals; however, a small number of newspapers, magazines, and newsletters considered useful to particular segments of the NLM broad user community have historically been included.

Availability: Searching MEDLINE via PubMed results in a list of citations (including authors, title, source, and often an abstract) to journal articles and links to the electronic full-text, if available. Searching PubMed is free of charge and does not require registration.

A growing number of MEDLINE citations in PubMed contain a link to the free full-text of the article archived in PubMed Central. Some MEDLINE citations also have publisher-provided links to the full-text of the article at the journal website; exact details depend on the publisher's access requirements.

PubMed data, including MEDLINE, can be downloaded as described on the Download PubMed Data page.

Last Reviewed: February 5, 2024