How to Cite Sources in Vancouver Citation Style

Vancouver citation style is the standard referencing system for biomedical and health sciences writing. It originated from a 1978 meeting in Vancouver, British Columbia, where a group of medical journal editors established the Uniform Requirements for Manuscripts Submitted to Biomedical Journals. That group eventually became the International Committee of Medical Journal Editors (ICMJE), and its recommendations now underpin the submission guidelines of thousands of medical journals worldwide, including The Lancet, The BMJ, and JAMA. If you are writing for a medical, nursing, or public health audience, Vancouver is very likely the style you need.

To format Vancouver references automatically, use the AllCitations Vancouver generator. For a comparison of all supported citation styles, visit the styles page.

How the Vancouver Numbered System Works

Like IEEE, Vancouver uses a numbered citation system rather than an author-date approach. Each source is assigned a number the first time it is cited, and that number is reused every time the source appears again. The reference list at the end of the paper is arranged in numerical order - that is, in the order the sources were first cited - not alphabetically.

The key difference from IEEE is how the numbers appear in the text:

• Superscript numbers are the most common format: "Recent studies have shown a significant reduction in mortality.^1" Some journals place the superscript after the punctuation mark; others place it before. Check your target journal's guidelines.
• Bracketed numbers are used by some journals as an alternative: "Recent studies have shown a significant reduction in mortality (1)." A few journals use square brackets [1] instead of parentheses.

General rules for in-text citations:

• Number sources consecutively in the order they first appear in the text, tables, and figures
• When citing multiple sources, separate the numbers with commas and use hyphens for consecutive ranges: ^1,3,5 or ^1-3
• If you cite source 4 again in a later section, it remains 4 throughout the paper
• Author names in the running text are optional. You may write "Smith et al.^4 demonstrated..." or simply "Previous research has demonstrated...^4"

Author Formatting Rules

Vancouver has specific conventions for listing authors that differ from both APA and IEEE:

• Name format: Surname followed by initials with no periods and no spaces between initials: Smith JK (not J. K. Smith, not Smith, J. K.)
• Up to 6 authors: List all authors, separated by commas
• More than 6 authors: List the first 6 authors followed by "et al."
• Organization as author: Write out the full organization name: World Health Organization

Author Limit Examples

The "first 6, then et al." rule is one of the most distinctive features of Vancouver style. APA 7 uses "et al." after the first author for works with three or more authors, and IEEE uses "et al." after the first author for six or more. Vancouver is more generous in listing individual contributors but draws a firm line at six.

Abbreviating Journal Titles

Vancouver style requires abbreviated journal titles in references. These abbreviations follow the National Library of Medicine (NLM) catalog, which is the same system used by PubMed and MEDLINE. You can look up the correct abbreviation in the NLM Catalog.

Note that NLM abbreviations do not use periods after abbreviated words (unlike IEEE abbreviations, which do). Single-word journal titles like Lancet and BMJ are not abbreviated further.

Worked Examples

Below are worked examples for the source types you will encounter most often in medical and health sciences writing. Each example shows the numbered reference list entry and a sample in-text citation.

Journal Article

Reference entry:

1. Chen L, Wang D, Patel R, Okonkwo E, Fernandez M, Sato T. Deep brain stimulation outcomes in treatment-resistant depression: a multicentre randomised controlled trial. Lancet Psychiatry. 2024;11(4):312-21. doi:10.1016/S2215-0366(24)00045-7.

In-text citation: ^1 or (1)

Key formatting points: authors listed as Surname Initials with no periods, abbreviated journal title without periods, year followed by a semicolon, volume, issue in parentheses, page range (truncated - "312-21" rather than "312-321"), and DOI.

Book

Reference entry:

2. Kumar V, Abbas AK, Aster JC. Robbins and Cotran pathologic basis of disease. 10th ed. Philadelphia: Elsevier; 2021.

In-text citation: ^2

Key formatting points: book title is not italicized in Vancouver (unlike most other styles). Include edition, place of publication, publisher, and year. Some journals do italicize book titles, so check your target publication's house style.

Book Chapter

Reference entry:

3. Torres LM. Pharmacological management of chronic pain. In: Wall PD, Melzack R, editors. Textbook of pain. 7th ed. Edinburgh: Churchill Livingstone; 2022. p. 456-89.

In-text citation: ^3

Key formatting points: the chapter title is followed by "In:" and the editors' names with "editors." after the last editor. Page range uses "p." (not "pp.").

Website

Reference entry:

4. World Health Organization. Cardiovascular diseases (CVDs) [Internet]. Geneva: WHO; 2023 [cited 2025 Mar 15]. Available from: https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds)

In-text citation: ^4

Key formatting points: add "[Internet]" after the title. Include the publication date and a "cited" date in square brackets. Use "Available from:" (not "Available at:") followed by the URL.

Clinical Guideline

Reference entry:

5. National Institute for Health and Care Excellence. Hypertension in adults: diagnosis and management. NICE guideline [NG136]. London: NICE; 2023 [cited 2025 Feb 10]. Available from: https://www.nice.org.uk/guidance/ng136

In-text citation: ^5

Key formatting points: treat guidelines like reports or web documents. Include the guideline number in square brackets, the publisher, and the access date.

Systematic Review from the Cochrane Library

Reference entry:

6. Bjelakovic G, Nikolova D, Simonetti RG, Gluud C. Antioxidant supplements for prevention of mortality in healthy participants and patients with various diseases. Cochrane Database Syst Rev. 2012;(3):CD007176. doi:10.1002/14651858.CD007176.pub2.

In-text citation: ^6

Key formatting points: Cochrane reviews follow the standard journal article format. The abbreviated journal title is "Cochrane Database Syst Rev." Include the review number (e.g., CD007176) and DOI.

Common Mistakes to Avoid

1. Alphabetizing the reference list. Like IEEE, Vancouver arranges references in citation order. The reference list should not be alphabetical.

1. Adding periods between author initials. Vancouver uses "Smith JK," not "Smith J.K." or "Smith, J. K." This is one of the most common formatting errors.

1. Writing out full journal titles. Always use the NLM-abbreviated journal title. Writing "The New England Journal of Medicine" instead of "N Engl J Med" is incorrect.

1. Listing more than 6 authors. If a source has 7 or more authors, list the first 6 and add "et al." Listing all authors is not only unnecessary but technically a formatting error.

1. Forgetting the access date for online sources. Vancouver requires a "cited" date in square brackets for any online source: [cited 2025 Mar 15].

1. Using italics for all titles. In strict Vancouver formatting, titles are generally not italicized. Some journals have adapted the style to include italics for book and journal titles, but the NLM/ICMJE default is no italics.

1. Confusing Vancouver with IEEE formatting. Both are numbered styles, but the author format (surname-first vs. initials-first), journal abbreviation system (NLM vs. ISO 4), and in-text number presentation (superscript vs. brackets) all differ. For a detailed IEEE guide, see our IEEE citation guide.

Vancouver vs. IEEE: A Detailed Comparison

Since both Vancouver and IEEE use numbered references, students in interdisciplinary programs sometimes mix them up. The table below highlights the key differences.

The easiest way to tell the two styles apart is the author format: if the surname comes first with no periods between initials (Smith JK), it is Vancouver; if initials with periods come first (J. K. Smith), it is IEEE.

Quick-Reference Table

For a full list of supported citation styles, visit the AllCitations styles page.