Skip to main content Chania


A guide to PubMed, an open-access database for health and biomedical research.

Welcome to the PubMed Research Guide!

Welcome to the Samuel C. Williams Library's PubMed research guide! This guide will help you learn how to use PubMed, a freely accessible database that comprises over 25 million citations for biomedical literature from MEDLINE, life science journals, and online books. PubMed citations and abstracts include the fields of biomedicine and health, covering portions of medicine, nursing, dentistry, veterinary medicine, the health care system, and the preclinical sciences.

What is PubMed?

PubMed is a citation database for the life sciences and biomedicine. It was created in 1996 and now contains more than 26 million references from the following components:

  1. MEDLINE: The National Library of Medicine's journal citation database, going back to the 1960s and including more than 23 million citations to articles from 1946-present. A journal's inclusion in MEDLINE is based on stringent standards to guarantee quality and relevance to the fields of biomed and life sciences. The full MEDLINE database is found in PubMed and all MEDLINE entries are indexed using the Medical Subject Headings (MeSH) taxonomy.
  2. PubMed Central (PMC): Since 2000, PMC has been a free archive for full-text articles that comply with the National Institute of Health's Public Access Policy, which was made a requirement for research funded by the NIH in 2008. To meet this requirement, authors or publishers must deposit some version of the final publication in PMC. Some publishers retain copyright on the work and make it publicly available only after an embargo period of some kind. There is some overlap between PMC and MEDLINE.
  3. NCBI Bookshelf: full-text of books and documents in life sciences and healthcare from the National Center for Biotechnology Information.

PubMed also includes citations from other, related sources. Much of what can be found in PubMed contains or links to full-text.

Source: U.S. National Library of Medicine. (2017). MEDLINE, PubMed, and PMC (PubMed Central): How are they different? [fact sheet]. Retrieved from