BMJ Formatting Requirements: Complete Author Guide

BMJ Research articles require a structured abstract of no more than 250 words. The required headings are:

• Objective (what the study aimed to do)
• Design (study type: RCT, cohort, cross-sectional, etc.)
• Setting (where the study was conducted)
• Participants (who was studied, with numbers)
• Interventions (if applicable)
• Main outcome measures (primary and secondary)
• Results (key findings with effect sizes and confidence intervals)
• Conclusions (what the results mean for practice)

The BMJ abstract structure is more granular than what you'll find at JAMA or The Lancet. Each section should be concise but specific. The Design section, for example, shouldn't just say "cohort study." It should specify "prospective population-based cohort study" or "retrospective matched cohort study."

In the Results section, always include effect estimates (odds ratios, hazard ratios, risk differences) with 95% confidence intervals and exact P values. The BMJ abstract is expected to contain enough quantitative detail that readers can assess the findings without reading the full paper.

The BMJ requires a title page as the first page of your manuscript. It must include:

• Manuscript title (informative, no abbreviations)
• All author names and affiliations
• Corresponding author details (name, address, email, phone)
• Word count (body text, excluding abstract and references)
• Abstract word count (listed separately)
• Number of figures and tables
• A "What this paper adds" box with 3-4 bullet points

The "What this paper adds" box is distinctive to the BMJ. It has two subsections:

What is already known on this topic:

• 2-3 bullets summarizing existing evidence

What this study adds:

• 2-3 bullets stating the new contribution

This box is published with the article and appears prominently. Write it carefully because it's one of the first things readers see. Each bullet should be one sentence, directly stated, with no hedging.

The BMJ doesn't impose a strict maximum on figures and tables, but editorial practice favors focused papers that don't overload the reader.

Figure requirements:

• Minimum resolution: 300 DPI for photographs, 600 DPI for line art
• Accepted formats: TIFF, EPS, JPEG, or PDF
• Maximum file size: 10 MB per figure
• Color is free for online publication; print may be grayscale
• Figures should be uploaded as separate files during submission
• Patient photographs require explicit written consent

Table requirements:

• Create tables in Word using the table function (not images or Excel screenshots)
• Every column must have a header
• Use footnotes for abbreviations and statistical notes
• Report confidence intervals and P values in tables, not just significance markers
• Avoid tables with more than 10 columns (split into multiple tables if needed)

Supplementary appendices:

The BMJ uses the term "supplementary appendices" (or "web appendices") for additional material published online. Large datasets, additional analyses, and supporting figures should go here. Supplementary content is peer-reviewed and permanently archived.

The BMJ uses Vancouver reference style, which is the most common format in biomedical publishing. If you've published in any medical journal, you likely know this style already.

Key formatting rules:

• Citations appear as superscript numbers in the text, placed after punctuation
• References are numbered consecutively in order of first appearance
• For papers with 1-6 authors, list all authors
• For papers with 7 or more authors, list the first 3 followed by "et al"
• Journal names are abbreviated according to NLM/MEDLINE standards
• Include DOIs when available

Example journal article (6 or fewer authors):

1. Davies NM, Holmes MV, Davey Smith G. Reading Mendelian randomisation studies: a guide, glossary, and checklist for clinicians. BMJ 2018;362:k601. doi:10.1136/bmj.k601.

Example journal article (7+ authors):

1. Patel R, Singh A, Kumar V, et al. Long-term cardiovascular outcomes after bariatric surgery. BMJ 2026;388:e074521. doi:10.1136/bmj-2025-074521.

Example book:

1. Rothman KJ, Greenland S, Lash TL. Modern Epidemiology. 4th ed. Wolters Kluwer; 2021.

Note that the BMJ uses a semicolon between volume and page number (362:k601) rather than a comma. Also, the BMJ has increasingly used article IDs rather than page numbers, so check the current format for recent BMJ articles.

This is one of the BMJ's most distinctive requirements. Every Research article must include a section titled "Patient and Public Involvement" describing how patients or members of the public were involved in the study.

The statement should address:

• Were patients involved in setting the research question or outcome measures?
• Were patients involved in the design of the study?
• Were patients involved in the recruitment or conduct of the study?
• Will results be disseminated to study participants?

If patients were not involved, you must explicitly state that. "No patients were involved in setting the research question or the outcome measures, nor were they involved in developing plans for the design or implementation of the study" is acceptable, but the BMJ editors prefer actual involvement.

This requirement reflects the BMJ's editorial commitment to patient-centered research. Papers that demonstrate genuine patient involvement in study design tend to be viewed more favorably during review.

The BMJ doesn't just recommend reporting guidelines. It requires them. Submitting without the appropriate completed checklist will result in an immediate return.

Required checklists by study type:

Download the appropriate checklist from the EQUATOR Network and complete it before submission. In the checklist, specify the page number or line number where each item is addressed in your manuscript.

The BMJ editors cross-reference these checklists against your manuscript. If you check "yes" for an item but the information isn't actually in the paper, your manuscript will be returned. Fill out the checklist honestly and use it as an editing tool to ensure completeness.

The BMJ practices open (signed) peer review. This doesn't directly change how you format your manuscript, but it affects the review process in ways authors should understand.

What open peer review means at the BMJ:

• Reviewer names are published alongside accepted papers
• Full reviewer reports (with author responses) are published in the paper's online supplement
• Reviewers know their comments will be public
• Authors should write responses to reviewers knowing they'll be published

This transparency tends to produce more constructive and detailed reviews. When you write your response to reviewers, be thorough and professional. Your response letter becomes a permanent part of the published record.

1. The "What this paper adds" box. This is published prominently with every Research article. It's not optional and isn't the same as the abstract. Think of it as the elevator pitch for your paper.

2. Patient involvement statement placement. This goes in the Methods section, not at the end of the paper. Include it as the final subsection of Methods.

3. Data sharing statement. The BMJ requires a data sharing statement specifying what data are available, to whom, and under what conditions. "Available upon reasonable request" needs to include the contact person and process.

4. Transparency declaration. The lead author must include a transparency declaration: "The lead author affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as originally planned have been explained."

5. Copyright and open access. BMJ Research articles are published under a Creative Commons CC-BY license. There's no choice of license for research articles. This means your paper is freely available immediately upon publication.

6. Competing interests format. The BMJ uses a standardized competing interests statement. Each author must complete the ICMJE disclosure form, and the statement published in the paper must match.

A BMJ Research article follows this structure:

1. Title page (title, authors, "What this paper adds" box, word counts)
2. Structured abstract (250 words, with Objective/Design/Setting/Participants/Interventions/Main outcome measures/Results/Conclusions)
3. Introduction (2-3 paragraphs, state the research question clearly)
4. Methods (study design, participants, data sources, outcomes, statistical analysis, patient involvement)
5. Results (organized to match the methods, with key figures and tables)
6. Discussion (principal findings, comparison with other studies, strengths and limitations, policy implications)
7. Conclusion (1 paragraph, state the main finding and its implication)
8. Data sharing statement
9. Transparency declaration
10. Author contributions
11. Funding
12. Competing interests
13. References
14. Figure legends
15. Tables
16. Supplementary appendices

The Discussion section at the BMJ has a specific expected structure. Start with principal findings (1 paragraph), then comparison with other studies (2-3 paragraphs), then strengths and limitations (1-2 paragraphs), then implications and future research (1-2 paragraphs). Editors look for this flow.

The BMJ has specific expectations for statistical reporting that go beyond most journals:

• Report exact P values (P = .032, not P < .05), except when P < .001
• Include 95% confidence intervals for all primary comparisons
• Use relative and absolute effect measures together (don't report only odds ratios)
• Report numbers needed to treat (NNT) when clinically appropriate
• Pre-specify primary and secondary outcomes; clearly label any post-hoc analyses
• Statistical software and version must be stated

For clinical trials, the BMJ requires the full CONSORT flow diagram showing participant flow from screening through analysis. This counts as one figure.

These errors cause the most delays at the BMJ:

• Missing the EQUATOR reporting checklist entirely
• Omitting the patient involvement statement
• Using "Background" instead of "Objective" as the first abstract heading
• Forgetting the "What this paper adds" box
• Not including a transparency declaration
• Reporting only relative effects without absolute measures
• Submitting without a data sharing statement
• Missing the competing interests disclosures for all authors
• Not following the structured Discussion format

For comparison with another major medical journal, see our JAMA formatting requirements guide. If you're still deciding between these journals, our BMJ vs JAMA comparison covers scope and editorial philosophy.

For the official and complete specifications, visit the BMJ author guidelines page.

In our pre-submission review work with manuscripts targeting the BMJ, four patterns generate the most consistent desk-rejection outcomes.

Patient and Public Involvement statement absent or pro forma. The BMJ author guidelines make PPI a mandatory field in the structured submission checklist; the system will not accept a submission where the PPI statement is blank. The guidelines require authors to describe specifically how patients or the public were involved in study design, conduct, reporting, or dissemination, or to explain why involvement was not appropriate for this study type. Generic statements ("patients were not involved") without any justification are flagged by the editorial office. For RCTs and large cohort studies, the BMJ increasingly expects active patient involvement at the design stage.

"What is already known / What this paper adds" summary box missing. BMJ Research articles must include a structured two-part summary box immediately after the abstract: "What is already known on this topic" (2-3 bullets) and "What this study adds" (2-3 bullets of the study's specific new contribution). This box is separate from the abstract and is not optional. Manuscripts that do not include it are returned as incomplete.

Structured abstract headings do not match BMJ format. The BMJ requires a structured abstract with these specific headings: Objective, Design, Setting, Participants, Main outcome measures, Results, Conclusions. Common substitutions that trigger returns include "Aim" instead of "Objective," "Materials and Methods" instead of "Design, Setting, Participants," or "Background" as an opening section. The heading format is enforced during technical check.

Reporting checklist submitted as blank or partially completed. The BMJ requires a completed EQUATOR checklist uploaded as a separate file. Reviewers check whether each item is addressed and the page number cited. Checklists where items are marked "N/A" without justification, or where the page-number column is left blank, generate revision requests before or during peer review.

A BMJ submission readiness check evaluates your PPI statement, summary box, abstract headings, and reporting checklist completeness against these patterns.