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PMC COVID-19 Collection FAQ

What is the PMC COVID-19 Collection?

Following the March 2020 call from the White House Office of Science and Technology Policy and science policy leaders of other nations, the National Library of Medicine (NLM) has been collaborating with publishers and scholarly societies to expand access via PubMed Central (PMC) to coronavirus-related publications and associated data. Through these collaborations, publishers voluntarily deposit articles identified as relevant to the COVID-19 pandemic or prior coronavirus research. Submitted publications are made available as quickly as possible after publication for discovery in PMC and through the PMC Open Access Subset for text mining, secondary analysis, and other types of reuse.

What publishers have contributed to the PMC COVID-19 Collection?

A list of collaborators and links to available publisher resources is available on the main PMC COVID-19 Collection page.

What is the scope of content accepted under the PMC COVID-19 Collection?

It is left to the discretion of the collaborating publishers and scholarly societies to determine which articles to deposit in PMC. Some publishers have selected articles related to coronaviruses broadly (e.g., including Sudden Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS)) or to the COVID-19 pandemic and SARS-CoV-2 virus, specifically. In addition to deposits of articles from biomedical journals, NLM has accepted articles from related disciplines as well.

Preprints are not accepted as part of the PMC COVID-19 Collection; however, preprints reporting NIH-supported COVID-19 research are added to PMC and PubMed under the NIH Preprint Pilot.

How is the deposit process for the PMC COVID-19 Collection different from standard PMC operations?

This collection makes use of general PMC infrastructure, policies, and procedures to the extent possible. Working within the established PMC infrastructure, NLM adapted its standard requirements for the deposit of individual articles and online-first articles to provide greater flexibility and ensure coronavirus research is available as quickly as possible. Further, interim PDF-only deposits are accepted in cases where the article PDF is published online prior to other formats being available.

NLM has also engaged with publishers and journals that do not currently participate in PMC but are in scope for the NLM Collection and wish to use PMC to make coronavirus-related research results available to the public.

What license terms are applied to articles deposited in the PMC COVID-19 Collection?

The license for each article deposited in the PMC COVID-19 Collection is at the discretion of the individual publishers and scholarly societies who deposit them. In some cases, articles are made available for reuse under a Creative Commons license (generally, Creative Commons with Attribution or CC BY). Articles that do not have a Creative Commons license include a custom license that allows for the article to be made available via the PMC Open Access Subset for re-use and secondary analysis.

As with all PMC Open Access Subset content, the license terms on these articles, including those with custom licenses, are not all identical. Please refer to the “Copyright and License Information” section on each article for specific terms of use.

Will PMC continue to provide perpetual access to the deposited articles?

As an archive, PMC will continue to provide perpetual access to all articles deposited in the PMC COVID-19 Collection for which the copyright holder provides such permission.

Should a copyright holder request content be removed from the archive, PMC will post an announcement noting the removal of content.

How can I find COVID-19 or coronavirus-related articles in PMC?

For the most complete results of articles in PMC on COVID-19, specifically, and coronaviruses, more broadly, we encourage you to use the search query links provided on the PMC COVID-19 Collection page in the section titled “Coronavirus-Related and COVID-19-Related Articles in PMC”.

Individuals interested in discovering all COVID-19-related literature in NLM literature databases should search each database individually (see the Literature section of Results may differ due to the availability of records in each database as well as the scope of what is available to search in each database (e.g., titles and abstracts vs. full text). To view PMC-only records to complement your PubMed search results, you may append your PMC search with “NOT pmc pubmed[filter].” (See also “Why are some articles from the PMC COVID-19 Collection not discoverable in PubMed?”)

Why are some articles from the PMC COVID-19 Collection not discoverable in PubMed?

NLM adapted its standard deposit requirements for the PMC COVID-19 Collection to allow for the submission of individual and online-first articles, allowing for greater flexibility and ensuring rapid availability of coronavirus-related research. In doing so, eligible publishers have been able to deposit articles in PMC from journals not currently in the NLM Collection, and thus not in the NLM Catalog. As PubMed indexing requires the presence of an NLM Catalog record, some article records are only searchable in PMC.

Additionally, articles published in MEDLINE journals may be deposited in PMC by publishers prior to citation data being deposited in PubMed.

Should authors continue to deposit manuscripts in compliance with the NIH Public Access Policy?

NLM encourages authors to deposit their eligible author manuscript that report research funded by NIH or other PMC partner funders via the NIH Manuscript Submission (NIHMS) system. As license terms vary for articles deposited to the PMC COVID-19 Collection, this ensures long-term public access to and preservation of this content in compliance with the NIH Public Access Policy.

NIH-funded researchers should continue to report the NIH research support of any articles or manuscripts via My Bibliography.

Last modified: Fri May 5 2023