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Instructions for authors

Editorial policies

BMJ Open is an open access journal dedicated exclusively to publishing medical research. The journal aims to provide rapid publication of research across a range of medical disciplines and therapeutic areas, through a continuous publication model. As well as publishing definitive articles, including small and specialist studies, BMJ Open will consider protocols and pilot studies. See here for more information on what we publish.

Submissions should be made through our online submission system. Submissions will only be published after peer review, and reviewers' comments will be published alongside accepted manuscripts.

Articles should not be under review, or submitted for review, with any other journal when submitted to BMJ Open. This includes other journals from BMJ.

Authors retain copyright; articles are published under a Creative Commons licence.

Open access
Authors retain copyright of their work. Articles are published under Creative Commons licences, including licences that meet RCUK and Wellcome Trust requirements. Our full licence is here.

Publishing in BMJ Open enables you to fulfil the open access requirements of the Wellcome Trust and Research Councils UK, including using their preferred CC BY licence.

Article publishing charges
BMJ Open levies an article publishing charge that reflects the true cost of the services provided. The charge is UK £1,350 (+VAT where applicable), US $2,200 or EUR 1,900. The charge for publishing a study protocol is £1,000 (+VAT where applicable), US $1,650 or EUR 1,450. There are no submission or page charges, and no colour charges. 

Your institution may already have arranged to cover your publishing costs or you may be eligible for a discount. Click here to find out.

In recognition of reviewers' support, any reviewer that returns a full review, on time, can receive a 25% discount on article publishing charges for a paper for which they are the corresponding author, if submitted within 12 months of completing the review.

We aim to publish articles in their final form within 3 weeks of acceptance (average currently less than 2 weeks); however, articles will not be published until payment has been received. We are unable to process cancellations, refunds or returns for article publication charges.

Waivers and discounts
We appreciate that some authors do not have access to funds; the journal will accept part payment where only limited funds are available, and offers waivers in exceptional circumstances on request. No payment information is requested before an article is accepted, so the ability to pay cannot affect editorial decisions. 

BMJ Open’s operations are maintained almost entirely by article publishing charges. We expect authors to exhaust all funding sources, including personal funds, before applying for a waiver or discount.

Requests for waivers and discounts will be considered using the following criteria:

•    Whether the research was conducted largely or entirely in a country that is in the Hinari Core Offer
•    Whether there was external funding for the research for any of the authors
•    Whether the authors could contribute from their personal accounts

Studies that are wholly or part funded by the tobacco industry
BMJ Open will not consider for publication any study partly or wholly funded by the tobacco industry, as explained here.

Submission policies

For guidelines on policy and submission across our journals, please click on the links below:

Manuscript preparation
Editorial policies
Patient consent forms
Licence forms
Peer review
Submission and production processes

Please note that in some cases BMJ Open has different submission requirements (e.g. there are no colour charges); where this is the case these are outlined below.

Article types

Research articles
Research submissions should have a clear, justified research question.
All articles should include the following.

  • The article title should include the research question and the study design. Titles should not declare the results of the study.
  • A structured abstract (max. 300 words) including all the following where appropriate (please note that for RCTs there is a specific CONSORT extension for abstracts):
    • objectives: clear statement of main study aim and major hypothesis/research question
    • design: e.g. prospective, randomised, blinded, case control
    • setting: level of care e.g. primary, secondary; number of participating centres. Generalise; don't use the name of a specific centre, but give geographical location if important
    • participants: numbers entering and completing the study; sex and ethnic group if appropriate. Clear definitions of selection, entry and exclusion criteria
    • interventions: what, how, when and how long (this can be deleted if there were no interventions)
    • primary and secondary outcome measures: planned (i.e. in the protocol) and those finally measured (if different, explain why) - for quantitative studies only
    • results: main results with (for quantitative studies) 95% confidence intervals and, where appropriate, the exact level of statistical significance and the number need to treat/harm. Whenever possible, state absolute rather than relative risks
    • conclusions: primary conclusions and their implications, suggest areas for further research if appropriate. Do not go beyond the data in the article
    • where applicable, trial registration: registry and number (for clinical trials and, if available, for observational studies and systematic reviews)
  • An 'Article summary' section consisting of the heading: 'Strengths and limitations of this study', and containing up to five short bullet points, no longer than one sentence each, that relate specifically to the methods of the study reported. They should not include the results of the study and should be placed after the abstract. 
  • The original protocol for the study, where one exists, as a supplementary file.
  • A funding statement, preferably worded as follows. Either: 'This work was supported by [name of funder] grant number [xxx]' or 'This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors'. You must ensure that the full, correct details of your funder(s) and any relevant grant numbers are included.
  • A competing interests statement. See this advice from the BMJ on what to include.
  • Articles should list each author's contribution individually at the end; this section may also include contributors who do not qualify as authors. Please visit the ICMJE website for more information on authorship.
  • Any checklist and flow diagram for the appropriate reporting statement, e.g. STROBE (see below).
  • Any article that contains personal medical information about an identifiable living individual requires the patient's explicit consent before we can publish it. We will need the patient to sign our consent form, which requires the patient to have read the article. This form is available in multiple languages.
  • Please provide a data sharing statement such as: "Technical appendix, statistical code, and dataset available from the Dryad repository, DOI: [include DOI for dataset here].

We recommend your article does not exceed 4000 words, with up to five figures and tables. This is flexible, but exceeding this will impact upon the paper's 'readability'. Supplementary and raw data can be placed online alongside the article although we prefer raw data to be made publicly available and linked to in a suitable repository (e.g. Dryad, FigShare). We may request that you separate out some material into supplementary data files to make the main manuscript clearer for readers.

We also recommend, but do not insist, that the discussion section is no longer than five paragraphs and follows this overall structure (you do not need to use these as subheadings): a statement of the principal findings; strengths and weaknesses of the study; strengths and weaknesses in relation to other studies, discussing important differences in results; the meaning of the study: possible explanations and implications for clinicians and policymakers; and unanswered questions and future research.

Authors are encouraged to submit figures and images in colour - there are no colour charges.

At upload you will be asked to choose one general subject area that applies to your article - it will be published under this banner on the main table of contents. You will also be asked to select further subject headings to be used for the 'Browse by topic' section, and specific keywords for help with identifying reviewers.

Reporting guidelines
The guidelines listed below should be followed where appropriate. Please use these guidelines to structure your article. Completed applicable checklists, structured abstracts and flow diagrams should be uploaded with your submission; these will be published alongside the final version of your paper.

The Equator Network (Enhancing the Quality and Transparency Of health Research) provides a comprehensive list of reporting guidelines.

Data sharing
See also our data sharing FAQs.

Study protocols

Protocol manuscripts should report planned or ongoing research studies. If data collection is complete, we will not consider the manuscript. 

Publishing study protocols enables researchers and funding bodies to stay up to date in their fields by providing exposure to research activity that may not otherwise be widely publicised. This can help prevent unnecessary duplication of work and will hopefully enable collaboration. Publishing protocols in full also makes available more information than is currently required by trial registries and increases transparency, making it easier for others (editors, reviewers and readers) to see and understand any deviations from the protocol that occur during the conduct of the study.

The SPIRIT (Standard Protocol Items for Randomized Trials) statement has now been published (see here for details). It is an evidence-based tool developed through systematic review of a wide range of resources and consensus. It closely mirrors the CONSORT statement and also reflects important ethics considerations. We encourage investigators to adhere to the SPIRIT recommendations when drafting their protocols.

The PRISMA-P (Preferred reporting items for systematic review and meta-analysis protocols) is a new reporting guideline. An article stating the guideline checklist has now been published (see here for details). The PRISMA-P checklist contains 17 items considered to be essential and minimum components of a systematic review or meta-analysis protocol. Systematic review authors and assessors are strongly encouraged to make use of PRISMA-P when drafting and appraising review protocols.

Various other resources exist that list the ingredients of an authoritative trial protocol, e.g. the UK Dept of Health/Medical Research Council Clinical Trials Toolkit and the US National Institutes for Health provide advice on how to structure a trial protocol. BMJ Open will consider for publication protocols for any study design, including observational studies and systematic reviews.

We strongly encourage you to register your study. Prospective registration is mandatory for any clinical trials. Acceptable registries for trials are listed here. We recommend Prospero for registration of systematic reviews.

General BMJ policies apply (see above) on manuscript formatting, editorial policies, licence forms and patient consent (where applicable to study designs). Protocols should include, as a minimum, the following items.

  • Protocol papers should report planned or ongoing studies. Manuscripts that report work already carried out will not be considered as protocols. The dates of the study must be included in the manuscript and cover letter.
  • Protocols for studies that will require ethical approval, such as trials, are unlikely to be considered without having received that approval.
  • Title: this should include the specific study type, e.g. randomised controlled trial.
  • Abstract: this should be structured with the following sections. Introduction; Methods and analysis; Ethics and dissemination. Registration details should be included as a final section, if appropriate.
  • Introduction: explain the rationale for the study and what evidence gap it may fill. Appropriate previous literature should be referenced, including relevant systematic reviews.
  • Methods and analysis: provide a full description of the study design, including the following. How the sample will be selected; interventions to be measured; the sample size calculation (drawing on previous literature) with an estimate of how many participants will be needed for the primary outcome to be statistically, clinically and/or politically significant; what outcomes will be measured, when and how; a data analysis plan.
  • Ethics and dissemination: ethical and safety considerations and any dissemination plan (publications, data deposition and curation) should be covered here.
  • Full references.
  • Authors' contributions: state how each author was involved in writing the protocol.
  • Funding statement: preferably worded as follows. Either: 'This work was supported by [name of funder] grant number [xxx]' or 'This research received no specific grant from any funding agency in the public, commercial or not-for-profit sectors'.
  • Competing interests statement.

Cohort profiles
The cohort profile is an article type set up in BMJ Open to fill the space between a study protocol and a results paper. Cohort profiles should describe the rationale for a cohort’s creation, its methods, baseline data and its future plans. Cohorts described should be long-term, prospective projects and not time-limited cohorts established to answer a small number of specific research questions.

If a cohort has yet to complete recruitment or baseline data collection, it should be submitted as a study protocol. Papers addressing a specific research question using cohort data should be submitted as a Research paper. 


Should begin ‘Cohort profile: …’. It should include the full name and any commonly used abbreviation of the cohort, plus its location or whether it is international. Include the type of cohort.


Use these headings to provide brief descriptions of the following:

  • Purpose: describe why the cohort was set up
  • Participants: describe who is in the cohort
  • Findings to date: what data has been collected so far and any major results
  • Future plans: how will the cohort be used in future, including any date for completion of data collection
  • Registration: BMJ Open only considers prospectively registered trials that comply with the recommendations of the International Committee of Medical Journal Editors (see here for details).


Describe the rationale for the study, including any specific research questions that motivated the project.

Cohort description

Describe the setting, locations and relevant dates, including periods of recruitment, exposure, follow-up and data collection.

Give the eligibility criteria and how participants were recruited. Report numbers of individuals at each stage of the study, e.g. how many were approached, included in the study and have been retained. Reasons for non-participation should be reported. A flow diagram is recommended to illustrate this.

Describe methods of data collection and follow-up, and any external data sources used.

Give characteristics of study participants (e.g. demographic, clinical, social) and information on exposures and potential confounders. Indicate number of participants with missing data for each variable of interest.

Detailed statistical plans should not be reported.

Findings to date

Include a short explanation of the most notable results from the cohort so far, with references to relevant publications. This section should summarise rather than present results.

Strengths and limitations

These should be specific to the cohort being described. Include any lessons learned from the cohort’s creation that can be shared to help future researchers.


Authors should include a section on what data will be available, to whom, how it can be accessed and what restrictions to reuse may apply. (This should be in the text, not the data sharing statement.) Please also state what kind of collaboration you are encouraging.

Further details
Our standard inclusions – Strengths and limitations of this study, a data sharing statement, funding declaration, contributorship statement, etc., should also be included. 

Pilot studies
Articles reporting pilot studies should explain the work's wider context and explain why the term 'pilot study' applies. The term 'pilot study' should not be applied to justify reporting a small-scale study. Justifications for a pilot study include:

  • trialling a new procedure intended for use in a larger programme of research
  • establishing power calculations required for a full-scale study
  • establishing how many patients and/or healthcare professionals can be recruited
  • evaluating the financial, technical, administrative or logistic feasibility of a full-scale study, including issues of data collection, protocol adherence, and questionnaire design.

The sample/patient size should still be justified. The article should explain the impact that the pilot study had on decisions regarding future research.

Rapid responses and online comments
We encourage readers to comment on articles published in BMJ Open. Please follow our guidelines set out in our Blog and eLetter response terms and requirements, available here. It is also possible to post less-formal comments online at the end of articles using the Disqus commenting facility.

Peer review process

All articles published in BMJ Open will have been sent for external, open peer review. Reviewers will not be asked to judge importance or breadth of appeal. Readers will be able to make these judgements for themselves. We recommend you use our instructions for reviewers as a checklist to ensure that your article is complete. Upon publication, all previous versions of the manuscript will also be made available, as will the reviewers' comments and authors' replies to those comments.

Post-publication peer review will also be possible via the Disqus comments, rapid responses and article level metrics, including the option for readers to rate the article positively or negatively.

BMJ Open will consider appeals on rejected manuscripts provided the authors can demonstrate that the decision on their manuscript was flawed or not in line with the journal's policies. For an appeal to be considered, authors must provide a detailed point-by-point response to all the concerns raised by the reviewers or editors involved with the manuscript. We ask that authors do not provide a revised manuscript during the appeal. All decisions made on appeals are final, and the decision process could take longer than with original submissions. Appeals must be made within 30 days of the reject decision.

Peer review of study protocols
BMJ Open will consider publishing without peer review protocols that have formal ethical approval and funding from a recognised, open access advocating research-funding body (such as those listed by the JULIET project). Please provide proof that these criteria are met when uploading your protocol. Any protocols that do not meet both these criteria will be sent for open external peer review, with reviewer comments published online upon acceptance, as with research articles. Reviewers will be instructed to review for clarity and sufficient detail. The intention of peer review is not to alter the study design. Reviewers will be instructed to check that the study is scientifically credible and ethically sound in its scope and methods, and that there is sufficient detail to instil confidence that the study will be conducted and analysed properly.

As with research articles, protocols will be published under a Creative Commons licence.


The journals from BMJ are willing to consider publishing supplements. Supplement proposals may be made at the request of:

  1. The journal editor, an editorial board member or a learned society may wish to organise a meeting, sponsorship may be sought and the proceedings published as a supplement.
  2. The journal editor, editorial board member or learned society may wish to commission a supplement on a particular theme or topic. Again, sponsorship may be sought.
  3. The BMJ itself may have proposals for supplements where sponsorship may be necessary.
  4. A sponsoring organisation, often a pharmaceutical company or a charitable foundation, that wishes to arrange a meeting, the proceedings of which will be published as a supplement.

In all cases, it is vital that the journal's integrity, independence and academic reputation is not compromised in any way. All supplements are fully peer-reviewed. For further information on criteria that must be fulfilled, download the supplements guidelines (PDF).

Plagiarism detection

BMJ is a member of CrossCheck by CrossRef and iThenticate. iThenticate is a plagiarism screening service that verifies the originality of content submitted before publication. iThenticate checks submissions against millions of published research papers, and billions of web content. Authors, researchers and freelancers can also use iThenticate to screen their work before submission by visiting

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