PubMed Central (PMC) is a free archive of full-text biomedical and life sciences journal literature at the U.S. National Institutes of Health's National Library of Medicine (NIH/NLM). It is a repository for journal literature deposited by participating publishers, as well as for author manuscripts that have been submitted in compliance with the NIH Public Access Policy and similar policies of other research funding agencies.
PMC has the capacity to store and cross reference data from different sources in a common format within a central repository, a PMC user can quickly search the entire collection of full-text articles and locate all relevant material.
Since its inception in 2000, PMC has grown from comprising only two journals;
PNAS: Proceedings of the National Academy of Sciences
Molecular Biology of the Cell
Participation by publishers in PMC is voluntary, although participating journals must meet certain scientific and technical standards. PMC, itself, is not a publisher and does not publish articles itself.
The currency and age of material in PMC varies by journal. Many journals make their content available in PMC as soon as it is published.
PubMed consists of more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
Some PMC journals are also MEDLINE indexed journals. For publishers, there are a number of ways to participate and deposit their content in this archive, explained on the NLM Web pages Add a Journal to PMC and PMC Policies. Journals must be in scope according to the NLM Collection Development Guidelines. Although free access is a requirement for PMC deposit, publishers and individual authors may continue to hold copyright on the material in PMC and publishers can delay the release of their material in PMC for a short period after publication. There are reciprocal links between the full text in PMC and corresponding citations in PubMed.
In conclusion, PubMed citations come from MEDLINE indexed journals, journals/manuscripts deposited in PMC and NCBI Bookshelf. Both MEDLINE and other PubMed citations may have links to full-text articles or manuscripts in PMC, NCBI Bookshelf, and publishers' Web sites. If we limit our PubMed search to MeSH controlled vocabulary or the MEDLINE subset, we will see only MEDLINE citations in our results.
The National Library of Medicine is making every effort to ensure that the information available on the Web site is accessible to all. Some parts of the PubMed Central archive may not be fully accessible to persons with disabilities, even with assistive technology. If you are a person with a disability or use assistive technology and encounter problems when using our site and its contents, it is asked to inform. The team will work with you to provide the information to you in an alternate format.
PMC journals and publisher programs
All content is freely available
Long-term preservation of the scientific literature