Gut Formatting Requirements: Complete Author Guide

Gut uses a structured abstract for original research with five headings.

• Word limit: up to 250 words

• Headings for Original Research:

• Background

• Objective

• Design

• Results

• Conclusion

• Citations: Not permitted (BMJ's formatting guidance says references should not be included in abstracts)

• Trial registration: BMJ will not consider reports of clinical trials unless they were registered prospectively, before recruitment of any participants

Use the headings Gut lists rather than headings borrowed from another journal.

The "Design" section should name the study design explicitly: "Prospective cohort study," "Randomized double-blind placebo-controlled trial," "Retrospective case-control study," etc.

Write the Results section with specific numbers: "Patients receiving treatment A showed a 42% reduction in disease flare rate (HR 0.58, 95% CI 0.41-0.82, P=0.002) compared with placebo over 52 weeks." Make sure the numerical claims in the abstract match the main text.

Gut does not cap figures for Original Research; the instructions say figures are not limited but must be thoroughly justified.

Figure specifications:

Color figures: BMJ offers colour publication online at no charge, but the figure legend must not refer to the use of colours. Authors can choose colour in the print edition instead of the default black and white for 510 GBP. Design your figures for color viewing, but ensure they're interpretable in grayscale as a fallback.

Table formatting: Tables should be in Word format and placed in the main text where the table is first cited, and cited in numerical order. Tables embedded as Excel files are not accepted. Tables should be self-explanatory, and the data they contain must not be duplicated in the text or figures. Any table longer than 2 pages is published as online-only supplementary material.

Supplementary figures and tables: Supplemental material is published online only, as supplied, and may or may not be peer-reviewed depending on the journal's editorial office. Cite it in the main text and upload it with the file designation "Supplementary File". Supplemental files may be PDF and should not exceed 350MB.

Endoscopy and histology images: For GI-specific figures, include scale bars on all histology images. For endoscopy images, note the scope type and magnification if relevant. High-resolution endoscopic images should be submitted at native resolution where possible.

Gut uses the Vancouver reference style, which is standard for BMJ journals.

In-text citations: Numbers assigned in order of first appearance, presented as superscripts or in square brackets (e.g., [6]). Multiple references separated by commas (e.g., [6, 9, 12]), sequential numbers joined with a hyphen (e.g., [12-15]).

Reference list format. Compare the Gut Vancouver format against the APA habit authors carry over from other journals:

Correct (Gut Vancouver; no periods between initials, abbreviated journal name, truncated page range):
1. Smith JA, Johnson BC, Williams DE. Title of article in sentence case. *Gut* 2025;**74**:123-8.
Wrong (APA habit: surname-comma-initials, parenthetical year, full page range):
Smith, J. A., Johnson, B. C., & Williams, D. E. (2025). Title of article in sentence case. Gut, 74, 123-128.

Key formatting details:

• Author names: Last name followed by initials, no periods between initials

• List the first 3 authors, then "et al." for papers with 4+ authors

• No comma between journal name and year

• Year followed immediately by semicolon and volume number

• Page ranges truncated (e.g., 123-8 not 123-128)

• Journal names abbreviated, as in BMJ's examples (for example Inj Prev)

• Include the DOI or PubMed ID, as BMJ's formatting guidance asks

The instructions limit references for Original Research to those critical and relevant to the manuscript (around 50).

One Vancouver-specific detail that catches authors: in the reference list, there are no periods after author initials. Write "Smith JA" not "Smith J.A."

Gut's online supplementary material is hosted alongside the article on the BMJ website.

What goes in the online supplement:

• Additional figures, tables, and datasets that exceed the main article limits

• Extended methods descriptions

• Sensitivity analyses and subgroup analyses

• CONSORT diagrams or PRISMA flow charts (often in the supplement if not in the main text)

• Videos (endoscopy footage, surgical procedures)

• Patient-level data summaries

Formatting rules:

• Reference each supplementary item in the main text

• Provide titles and legends for all supplementary figures and tables

• Video files are preferred in .WMF or .AVI format, and can also be supplied as .FLV, .Mov, or .MP4, uploaded with the file designation "Supplementary File - Video"

• Supplemental material may or may not be peer-reviewed, and it is published as supplied, without checking, copyediting or proofing

• The reporting checklist is uploaded as a separate file titled "Research Checklist", not as supplementary material

Data sharing: Gut follows BMJ's Tier 3 data policy. All research articles must contain a Data Availability Statement, and the journal strongly encourages that the data behind your article be made available as soon as possible, wherever legally and ethically possible. The statement should specify what data are available and how to access them.

BMJ's data sharing policy points to recognised repositories such as Dryad, OSF, Figshare, Zenodo and Science Data Bank for general data, subject-specific repositories such as GenBank for pre-clinical data, and controlled-access repositories for clinical participant data.

Gut's instructions refer to a title page (word counts exclude it). BMJ takes author names, institutions and addresses from the fields you complete in the submission system, not from the submitted Word document.

What to include on the title page and in the submission:

• A title that includes the research type (the instructions ask you to include the research type in your title)

• All author names, with an up-to-date name, email address and institutional affiliation for each contributing author entered in the submission system

• Corresponding author contact details

• Keywords, using MeSH descriptors where possible (BMJ asks authors to use MeSH descriptors as keywords)

Separate declarations (in the manuscript or submission system):

• Competing interests statement

• Funding statement

• Ethics approval statement with committee name and approval number

• Patient and public involvement statement (BMJ-specific requirement)

• Contributorship statement (who did what in planning, conducting and reporting the work)

Patient and public involvement (PPI) statement: Gut requires authors of Research Articles to add a Patient and Public Involvement statement in the Methods section, under the subheading "Patient and public involvement". You must describe whether patients or members of the public were involved in the design, conduct, reporting, or dissemination of the research. If they weren't involved, say so explicitly: "Patients or the public were not involved in the design, conduct, reporting, or dissemination plans of this research."

This PPI requirement surprises authors who are used to other publishers. It's not a formality: if the statement is missing from the submitted manuscript, the journal will ask you to provide it.

For manuscripts targeting Gut, four patterns generate the most consistent desk-rejection outcomes.

Abstract exceeds the Gut word limit or uses wrong structured headings. Gut uses structured abstracts with a 250-word limit and the headings Background, Objective, Design, Results, and Conclusion. Papers using another journal's headings (for example Methods) or exceeding the word limit can be sent back for correction during the pre-review quality checks. The structured format applies to original research.

Significance statement for GI or liver biology not translated to clinical implication. Gut publishes at the interface of gastrointestinal science and clinical practice. Papers that present mechanistic or basic science findings without articulating the clinical implication for gastroenterology, hepatology, or IBD management are desk-rejected unless the mechanistic advance is truly exceptional. The journal describes its coverage as clinically oriented.

Reporting checklist absent for trial or observational design. BMJ asks that research articles follow the relevant reporting guideline, for example CONSORT for randomized trials, STROBE for observational studies, and PRISMA for systematic reviews. The checklist is submitted as a file titled "Research Checklist" that lists the page on which each item appears. A missing checklist can hold up the pre-review quality checks in ScholarOne Manuscripts.

Microbiome data lacks sequencing-depth controls and compositional analysis. For microbiome papers, reviewers in this area commonly look for rarefaction curves showing adequate sequencing depth, alpha- and beta-diversity analysis, compositional-aware analysis (e.g., ANCOM, ALDEx2) rather than naive fold-change, and delineation of the exact sequencing platform and primers used.

Across these four patterns, the common thread in our review work is that the gastroenterology science is usually strong but a BMJ-specific convention is missing. The abstract uses the wrong structured headings, the significance box never translates the mechanism into a clinical implication, the reporting checklist is absent, or the microbiome methods and statistics fall short of the compositional standard.

Each is a formatting-and-rigor convention that is fixable in the manuscript before submission rather than discovered as an administrative return through ScholarOne.

A Gut submission readiness check evaluates manuscript scope, BMJ abstract format, and microbiome reporting standards against these desk-rejection patterns.