Preprints (the pre-review manuscript that is submitted to a journal, or any earlier draft) aim to improve the openness and accessibility of scientific findings. They allow authors to make their findings immediately available to the health sciences community and receive feedback on draft manuscripts before they are submitted to journals for formal publication. This can enhance collaboration among researchers, document provenance of ideas and inform ongoing and planned research.
Preprints are preliminary reports of work that have not been peer reviewed. They should therefore not be used to guide clinical practice, health-related behavior or health policy. They should not be reported in the media as established information.
BMJ preprint policy
BMJ fully supports and encourages the archiving of preprints in any recognised, not-for-profit, preprint server. The BMJ and BMJ Journals do not consider the deposition of preprints in dedicated preprint repositories at the same time as, or before, submission to a journal to be prior publication.
Please note that this policy does not extend to case reports due to patient confidentiality concerns. BMJ will therefore not accept case reports which have been previously submitted to a preprint server.
Authors must provide the digital object identifier (DOI) to the preprint version of their manuscript when submitting to a BMJ journal (e.g https://doi.org/10.1101/2020.06.24.20138198).
Please see our self-archiving policy for more details of where you may post the different versions of your work.
If your article is accepted for publication in a BMJ Journal and selected for press release by BMJ, we ask that you make us aware if it has been published as a preprint and/or has already been publicised in any way, including on social media. Extensive media coverage prior to formal publication in a journal may mean that the article is not suitable for press release by BMJ.
How to submit a preprint
Preprints may be submitted directly to any recognised preprint server.
Author Accepted Manuscripts should not be placed on preprint servers. This helps to ensure the validity and integrity of the scientific record as readers are alerted to further versions, corrections, or retractions through technology contained in the Version of Record.
BMJ places no restrictions on the licence chosen when posting a preprint version of work (e.g. authors may choose CC BY or CC BY NC), but authors must retain copyright of their work when posting to a preprint server.
Upon publication of your article many preprint servers, including medRxiv, will automatically add a link to the published version. For servers that do not provide this service, upon publication of your article by a BMJ Journal, please add the following text to your preprint:
“This article has been published in [insert full citation] following peer review and can also be viewed on the journal’s website at [insert DOI].
BMJ is a founding partner of medRxiv, an independent preprint server for the clinical research community. Our partnership with medRxiv enables us to offer the direct transfer of manuscripts from medRxiv to all BMJ journals.
When submitting a preprint at medRxiv, authors are offered the option to automatically submit their paper to any BMJ journal. This process immediately transfers all manuscript files and author submitted metadata, reducing the requirement for authors to complete multiple submissions across multiple systems.
This service can be accessed from the Author area on MedRxiv after the submission of a preprint. Upon initiating a transfer, the author will receive an email from the BMJ submission system – ScholarOne Manuscripts – advising them on how to finalise the transfer. Articles may be submitted prior to, or concurrently with, submission to a journal but will not be posted if it has already been accepted or published elsewhere.
How to cite preprints
Preprint citations should include the author name(s), title, preprint server, the Preprint] ‘tag’, the document version (e.g. most recent date modified), the date the preprint was cited, the Digital Object Identifier (DOI) and should follow the BMJ reference style.
Example: Rostami A, Sepidarkish M, Leeflang M, et al. First snap-shot meta-analysis to estimate the prevalence of serum antibodies to SARS-CoV-2 in humans. MedRxiv 20185017 [Preprint]. September 02, 2020 [cited 2020 Sep 20] https://doi.org/10.1101/2020.08.31.20185017.