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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 will only be published after peer review, and reviewers’ comments will be published alongside accepted manuscripts.
BMJ Open will not consider for publication any study partly or wholly funded by the tobacco industry, as explained here.
BMJ Open adheres to the highest standards concerning its editorial policies on publication ethics, scientific misconduct, consent and peer review criteria. To view all BMJ Journal policies please refer to the BMJ Author Hub policies page.
Articles are published under a Creative Commons licence to facilitate reuse of the content and authors retain copyright; please refer to the BMJ Open Copyright Author Licence Statement.
Article publishing charges
BMJ Open is an open access journal and levies an Article Publishing Charge (APC) of 1,350 GBP (exclusive of VAT for UK and EU authors and GST for Australian and Indian authors) for all article types. There are no submission, colour or page charges.
No payment information is requested before an article is accepted, so the ability to pay cannot affect editorial decisions. Accepted articles will not be published until payment has been received. BMJ does not refund APCs once paid.
For more information on open access, funder compliance, discounts and waivers please refer to the BMJ Author Hub open access page.
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.
How can I maximise my chances of being published?
BMJ Open will publish all submissions judged to be technically sound after peer review. Asking yourself these five questions will help maximise your chances of a successful submission.
- Does my research fall within BMJ Open’s aims and scope?
- Is the research question clear?
- Is the study design appropriate?
- Is the study valid?
- Is the research presented correctly?
These are intended to be aids to a successful submission and reflect the type of judgement we ask reviewers to make. See exactly what reviewers will be asked here. If you have any questions please contact the editorial office.
Where can I find more general advice?
The pages above all contain useful information for anyone preparing a research article for BMJ Open. The following links provide more detailed information on how to perform and report research. The links are not exhaustive and if you know of any good resources we have not listed, please let us know.
Resources for data management and sharing
BMJ Open supports the idea that all appropriate datasets should be placed in open repositories. To assist, we have assembled some useful links and resources that cover best practice for data management plans through to sharing and citing complete datasets.
Please review the below article type specifications including the required article lengths, illustrations, table limits and reference counts. The word count excludes the title page, abstract, tables, acknowledgements, contributions and references. Manuscripts should be as succinct as possible.
For further support when making your submission please refer to the resources available on the BMJ Author Hub. Here you can also find general formatting guidelines across BMJ and a formatting checklist.
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, placed after the abstract, 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. They should not include the results of the study.
- 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 the BMJ Author Hub for details on what to include as competing interests.
- 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).
- A patient consent form: 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.
- A data sharing statement, such as: “Technical appendix, statistical code, and dataset available from the Dryad repository, DOI: [include DOI for dataset here]. /li>
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.
We require that you upload your figures as separate files rather than embedding them in the manuscript.
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.
Following the lead of The BMJ and its patient partnership strategy, BMJ Open is encouraging active patient involvement in setting the research agenda.
We appreciate that not all authors of research papers will have done this, and we will still consider your paper if you did not involve patients at an early stage. We do, however, request that all authors provide a statement in the methods section under the subheading Patient and Public Involvement.
The Patient and Public Involvement statement should provide a brief response to the following questions, tailored as appropriate for the study design reported:
- At what stage in the research process were patients/public first involved in the research and how
- How were the research question(s) and outcome measures developed and informed by their priorities, experience, and preferences?
- How were patients/public involved in the design of this study?
- How were they involved in the recruitment to and conduct of the study?
- Were they asked to assess the burden of the intervention and time required to participate in the research?
If patients were not involved please state this.
In addition to considering the points above we advise authors to look at guidance for best reporting of patient and public involvement as set out in the GRIPP2 reporting checklist.
Even if patients were not involved in the study described, we suggest that you consider enlisting their help in disseminating the research findings.
If this information is not in the submitted manuscript we will ask you to provide it during the peer review process.
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.
For reporting of randomised controlled trials: please use the appropriate extension to the CONSORT statement, including the extension for writing abstracts
For reporting qualitative research
For reporting qualitative research
For reporting of diagnostic accuracy studies
For reporting of observational studies in epidemiology
Checklist for cohort, case-control, and cross-sectional studies (combined)
Checklist for cohort studies
Checklist for case-control studies
Checklist for cross-sectional studies
For reporting of systematic reviews
For reporting of systematic review and meta-analysis protocols
For reporting of meta-analyses of observational studies
For reporting protocols for RCTs
For reporting of gene-disease association studies
For reporting of studies developing, validating, or updating a prediction model, whether for diagnostic or prognostic purposes.
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.
- An Article Summary, placed after the abstract, 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.
- 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.
- Word Count: Not applicable
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.
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.
Our standard inclusions – Strengths and limitations of this study, a data sharing statement, funding declaration, contributorship statement, etc., should also be included.
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
The BMJ Publishing Group journals are willing to consider publishing supplements to regular issues. Supplement proposals may be made at the request of:
- 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.
- 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.
- The BMJPG itself may have proposals for supplements where sponsorship may be necessary.
- 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.
For further information on criteria that must be fulfilled, download the supplements guidelines.
When contacting us regarding a potential supplement, please include as much of the information below as possible.
- Journal in which you would like the supplement published
- Title of supplement and/or meeting on which it is based
- Date of meeting on which it is based
- Proposed table of contents with provisional article titles and proposed authors
- An indication of whether authors have agreed to participate
- Sponsor information including any relevant deadlines
- An indication of the expected length of each paper Guest Editor proposals if appropriate