If you are writing for a medical, nursing, or biomedical science journal, there is a strong chance the submission guidelines say "follow Vancouver style" or "follow ICMJE recommendations." Vancouver is the most widely used citation system in clinical and health sciences publishing, and understanding it properly is essential for anyone submitting to journals indexed in PubMed, MEDLINE, or Embase.
The system takes its name from a 1978 meeting of medical journal editors in Vancouver, Canada, and is maintained today through the Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals published by the International Committee of Medical Journal Editors (ICMJE, 2023). This guide covers the rules, shows you the exact format templates, and explains the mistakes that lead to desk rejections.
Vancouver is a numbered citation system. Each source receives a number in the order it is first cited in the text. The number appears as a superscript or in parentheses or brackets, depending on the journal's house style. The reference list at the end of the document lists entries in numerical order — not alphabetical.
Several studies have confirmed this association.¹⁻³
Or:
Several studies have confirmed this association (1-3).
When the same source is cited again later in the text, it keeps its original number. New sources receive the next sequential number.
Key principle: Once a source is assigned a number, that number stays the same throughout the entire document. The reference list is ordered by first appearance, not by author name.
The reference list appears at the end of the document under the heading "References." Entries are numbered to match their in-text citations and are not sorted alphabetically.
Author names: Last name first, followed by initials with no periods and no spaces between initials. Up to six authors are listed; if there are seven or more, list the first six followed by "et al."
Article titles: Sentence case — only the first word and proper nouns are capitalised.
Journal names: Abbreviated according to the NLM Catalog (the same abbreviation system used in PubMed/MEDLINE). Do not spell out journal names in full.
DOIs and PMIDs: Include a DOI when available, formatted as https://doi.org/xxxxx. PMIDs may be appended for indexing purposes but are not required by ICMJE.
Author(s). Article title. Abbreviated Journal Name. Year;Volume(Issue):Pages.
DOI
Example — standard article:
Yancy CW, Jessup M, Bozkurt B, Butler J, Casey DE Jr, Drazner MH, et al.
2013 ACCF/AHA guideline for the management of heart failure. J Am Coll
Cardiol. 2013;62(16):e147-239. https://doi.org/10.1016/j.jacc.2013.05.019
Example — article with six or fewer authors:
Sterne JAC, Savovic J, Page MJ, Elbers RG, Blencowe NS, Boutron I.
RoB 2: a revised tool for assessing risk of bias in randomised trials.
BMJ. 2019;366:l4898. https://doi.org/10.1136/bmj.l4898
Author(s). Title of book. Edition. Place of publication: Publisher; Year.
Example:
Kasper DL, Fauci AS, Hauser SL, Longo DL, Jameson JL, Loscalzo J, editors.
Harrison's Principles of Internal Medicine. 20th ed. New York: McGraw-Hill
Education; 2018.
Author(s) of chapter. Title of chapter. In: Editor(s), editors. Title of
book. Edition. Place: Publisher; Year. p. Pages.
Example:
Meltzer PS, Kallioniemi A, Trent JM. Chromosome alterations in human solid
tumors. In: Vogelstein B, Kinzler KW, editors. The Genetic Basis of Human
Cancer. 2nd ed. New York: McGraw-Hill; 2002. p. 93-113.
Author/Organisation. Title [Internet]. Place: Publisher; Date [cited Year
Month Day]. Available from: URL
Example:
World Health Organization. WHO guidelines on physical activity and sedentary
behaviour [Internet]. Geneva: WHO; 2020 [cited 2024 Jan 10]. Available from:
https://www.who.int/publications/i/item/9789240015128
Issuing Organisation. Title of guideline. Guideline number. Place: Publisher;
Year. Available from: URL
Example:
National Institute for Health and Care Excellence. Hypertension in adults:
diagnosis and management. NICE guideline NG136. London: NICE; 2019.
Available from: https://www.nice.org.uk/guidance/ng136
Author(s). Title of paper. In: Editor(s), editors. Title of conference
proceedings; Date of conference; Place of conference. Place of publication:
Publisher; Year. p. Pages.
Vancouver references are numbered in order of first citation — not sorted alphabetically. This is one of the most common errors when switching from APA or MLA to Vancouver.
Vancouver requires abbreviated journal names from the NLM Catalog. Writing "Journal of the American Medical Association" instead of "JAMA" or "The New England Journal of Medicine" instead of "N Engl J Med" is incorrect.
Vancouver omits periods and spaces from author initials: "Smith JA" not "Smith, J. A." or "Smith J.A."
Vancouver lists up to six authors; seven or more triggers "et al." after the sixth name. AMA uses a different threshold (et al. after three). Applying AMA rules to a Vancouver reference is a frequent cross-style error.
If a DOI exists, include it. Many older articles now have DOIs assigned retrospectively — search doi.org by article title to check.
Adding or removing references during revision can break your numbering sequence. Always renumber references from scratch before final submission.
The NLM Catalog at catalog.nlm.nih.gov is the authoritative source for journal abbreviations in Vancouver style. Abbreviations follow ISO 4 conventions with NLM-specific modifications. Key points:
Practical tip: Export citations directly from PubMed in Vancouver format. The exported file contains verified journal abbreviations, PMIDs, and DOIs — eliminating the most common transcription errors.
The definitive source for Vancouver style is the ICMJE Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals (ICMJE, 2023), freely available at icmje.org. The NLM's Citing Medicine guide (Patrias & Wendling, 2007) provides additional detail on formatting specific source types and is available at ncbi.nlm.nih.gov/books/NBK7256/.
Formatting references in Vancouver style manually — tracking citation numbers, looking up journal abbreviations, handling the et al. threshold — is time-consuming and error-prone, especially for systematic reviews or multi-author manuscripts with hundreds of references.
DEEPNOTIS automates this process: paste a DOI or PMID and the platform retrieves verified metadata from PubMed and CrossRef, including the correct NLM journal abbreviation, full author list, volume, issue, pages, and DOI. Switch between Vancouver and other medical citation styles with a single click.
For large projects, citation labels let you organise sources by study design, risk-of-bias rating, or topic before exporting the final reference list — keeping your bibliography manageable regardless of size.
Getting Vancouver formatting right is not optional in medical publishing. Having a tool that enforces it automatically is what makes it practical at scale.
International Committee of Medical Journal Editors. (2023). Recommendations for the conduct, reporting, editing, and publication of scholarly work in medical journals. http://www.icmje.org/icmje-recommendations.pdf
Patrias K, Wendling D, technical editor. Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet]. 2nd ed. Bethesda (MD): National Library of Medicine (US); 2007. Available from: https://www.ncbi.nlm.nih.gov/books/NBK7256/
National Library of Medicine. NLM Catalog: Journals referenced in the NCBI databases [Internet]. Bethesda (MD): NLM. Available from: https://www.ncbi.nlm.nih.gov/nlmcatalog/journals