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On this page you will find, by scrolling down, our advice on:

• the BMJ's publishing model
• abridged research articles (for the print BMJ)
• web extras
• corrections
• previous publication and eprints
• netprints
• redundant publication
• duplicate publication
• simultaneous submission of manuscripts to more than one journal
• plagiarism

The BMJ's publishing model

The BMJ publishes its articles continuously to bmj.com, so each day there is new content (see Frequently asked questions). All BMJ original research articles are published with open access at no charge to authors or readers, and so are other articles where the work was funded by a grant with an open access mandate.

We select articles from bmj.com to make up each weekly print issue. When the print issue appears (every Friday) the PDFs are available on bmj.com together with links to the online articles that are also contained in that week’s print issue. We are thus ensuring a daily flow of topical content, including up to date research, while also providing (in the print issue) a weekly selection for those readers who prefer to have their content neatly packaged.

Each online article has a unique identifier, in place of a page number; this identifier (elocator) should be used when citing any BMJ article. The form of the citation—eg BMJ 2008;337:a134—appears on all articles both online and in print, and it will appear thus in PubMed and other indexes.

An article on bmj.com represents the full publication of that article. At the time of posting the bibliographic information is forwarded to PubMed and other indexing agencies, so the article can be searched for and found on bibliographical databases and can be cited as published (the citation format appears at the top of the online article).

In the print BMJ some articles are abridged, particularly original research articles.

Abridged research articles

The full text of all accepted BMJ research articles is published online in full, with open access and no word limit, on bmj.com as soon as it is ready. In the print BMJ each research article is abridged, with the aim of making research more inviting and useful to readers.

BMJ pico is our one page abridged format for research papers in the print journal, which some authors volunteered to help us pilot. We have designed BMJ pico with evidence based medicine experts to succinctly present the key evidence from each study, to help minimise delay between online and print publication, and to enable us to publish more research in each week’s print BMJ. See frequently asked questions (FAQs) about BMJ pico.

There is no need for authors to prepare a BMJ pico to submit along with their full research article. Authors produce their own BMJ pico, using a template from us, only after the full article has been accepted.

Because publication of research on bmj.com is definitive, rather than interim “epublication ahead of print”, authors who do not wish to abridge their articles using BMJ pico will be able to opt for online only publication.

Web extras

We do not set fixed limits for the length of the long version of BMJ research articles and we can be flexible about this. Nonetheless, please try to make your article concise and make every word count. Think hard about what really needs to be in the paper to get your message across accurately and what can be left out.

For research articles everything necessary to understand the research should be in the long version of the article. If you would like us to provide links from your BMJ research article to relevant supplementary material  - for example additional tables, boxes, and documents - on another website please let us know.

We may use bmj.com to add value to non-research articles (for example editorials and articles for the clinical review and education and debate sections) by publishing additional electronic material, including tables, boxes, and appendices. This material is not edited by the BMJ, and will be marked as “posted as supplied by author”. Once web extras have been posted on bmj.com they cannot be changed.

We also publish on bmj.com from time to time unedited background papers that relate to papers we are publishing. These do not appear in the print journal.

Corrections

We try hard not to make mistakes, but errors—both by editors and authors—do creep into the journal. We publish corrections when necessary, and, to ensure that corrections are handled consistently, one technical editor deals with them all.

We correct even minor mistakes, and we set no time limit for notifying errors or publishing corrections. We always try to contact the author of the original article unless the error is very obvious, and we publish all corrections as soon as we can.

If your article is published on bmj.com, and you discover a mistake between online and print publication we will normally correct this by making the article correct in the printed version and by reposting a new version of the article at the time of print publication. Only in exceptional circumstances will we publish a corrected version of an article between online and print publication.

In the print journal we publish corrections either singly in the relevant section or, more usually, grouped together in a box of "Corrections and clarifications." On bmj.com we indicate in red that an article has a correction and provide a direct link to it.

If you want further advice about our policy or would like to notify us about the need for a specific correction please email Julia Thompson. Please give as much detail as possible about errors, including any views on how they might have arisen.

Previous publication and electronic preprints (eprints) 

The BMJ does not want to publish material that has already appeared in full elsewhere. But we sometimes accept articles that have been published as abstracts or have been partially reported by the media at scientific meetings, and some that have already appeared in foreign language journals.

Previous publication in electronic form in certain settings may be acceptable, too. For example, the BMJ does not consider posting of protocols or results in clinical trials registries to be prior publication.

Before submitting material for publication authors often ask colleagues and peers for comments on the completed work. These unpublished articles are known as preprints. And, increasingly, authors are conducting this informal peer review using electronic preprints (eprints), often by posting the articles on websites and repositories.

In all these cases we expect authors to tell us about previous publication and to supply us with copies of such previous versions. Then we can assess whether publication in the BMJ will add usefully to the medical literature, or whether it will just add redundant material.

Netprints

Another way to expose original research articles to fellow researchers is to post them as netprints on a dedicated website before, during, or after peer review by other agencies. The BMJ Publishing Group and Stanford University Libraries' HighWire Press have such a website for articles on clinical medicine and health. This site will usually post articles within 24-48 hours of receipt. Articles will be screened to ensure that they report original research, and that they don't breach patient confidentiality or libel anyone, and that informed consent has been obtained from all participants (research subjects). The site gives full directions on how to post articles; authors do not need any special web skills. After posting, authors may update their articles as often as they like; all versions will be accessible from the netprint server. We hope that authors submitting a new article to the BMJ will also post it on this site. That way, anyone interested in new work will be able to read it in full, free, and immediately - whether or not the BMJ eventually decides to publish the article. Posting a netprint is entirely voluntary and is completely separate from  submission to the BMJ. We encourage, but don't require authors to use the netprint server.

The appearance of an article on the Netprints site does not imply approval of its assumptions, methods, or conclusions. Each netprint will be prefaced by this disclaimer: articles appearing on this site have not yet been accepted for publication by a peer reviewed journal. They are presented here mainly for the benefit of fellow researchers. Casual readers should not act on their findings, and journalists should be wary of reporting them.

Redundant publication

To save readers and researchers from being overwhelmed by redundant material we do not want to publish articles that overlap substantially with articles published elsewhere. We want to make up our own minds on the degree of overlap. Whenever an article submitted to the BMJ overlaps by more than 10% with previously published work, or work submitted elsewhere, we expect authors to send us copies of those articles. 
 
Duplicate publication

Duplicate publication is the publication of the same article or substantially similar articles in more than one journal. Authors must explain in the submission letter any prior publication of the same or substantially similar article, and should explain any circumstances that might lead the editor or reviews to believe that the article may have been published elsewhere (for example, when the title of a submitted article is the same as or similar to the title of a previously published article).

If the editor learns that a submitted article has been published elsewhere (in either the same or substantially similar form), the editor reserves the right to consult with other editors about the content of the articles in question. Further, the editor may return the article unreviewed, may consider no articles by any of the authors for a period of time, may announce publicly in the journal (perhaps as a simultaneous announcement with the editor of the journal that published the earlier article) that the authors have submitted a previously published article, or may do any combination of these actions, at the editor’s discretion.

If the article is accepted and published before the duplication is discovered, the editor will announce the duplication in the journal or have the authors write a letter acknowledging the duplicate publication, and the editor will notify the authors’ employers, at the editor’s discretion.

Simultaneous submission of manuscripts

Authors may not send the same manuscript to more that one journal at the same time. If the editor learns of possible simultaneous submission, the editor reserves the right to consult with the other editor(s) who have received the article. Further the editor may return the artcile without review, or may reject it without regard to the reviews, or make this decision in discussion with the other editor(s) involved, and may decide to consider no articles from the author from the authors for a period of time, and may also write to the authors' employers, or may do any combination of these actions, at the editor’s discretion.

Plagiarism

Plagiarism is the use of others’ published and unpublished ideas or words (or other intellectual property) without attribution or permission, and presenting them as new and original rather than derived from an existing source. The intent and effect of plagiarism is to mislead the reader as to the contributions or the plagiariser. This applies whether the ideas or words are taken from abstracts, research grant applications, ethics committee applications, or unpublished or published manuscripts in any publication format (print or electronic). Plagiarism is serious scientific misconduct.