Vancouver Referencing: A Quick Guide with Clear Examples

The Vancouver referencing style was developed by the International Committee of Medical Journal Editors (ICMJE). It is widely used in medicine, nursing, biomedical sciences, and other scientific fields. Vancouver uses a numeric citation system, where each source is assigned a number in the order it appears in your text. The number may be shown in round brackets (1) or as superscript¹ depending on your institution’s guidelines.

Vancouver In-text Citation Examples

Each source receives a number the first time it appears in your writing. The same number must be used every time you refer to that source later in the text.

You can cite the source in three main ways:

Citation at the end of a sentence
Digital health apps can improve patient self-monitoring (1).
– or –
Digital health apps can improve patient self-monitoring.¹

Citation integrated into the text
A recent study (1) found that remote monitoring tools help reduce hospital visits.
– or –
A recent study¹ found that remote monitoring tools help reduce hospital visits.

Mentioning the author in the sentence
According to Lopez (1), wearable devices can help track long-term health trends.
– or –
According to Lopez¹, wearable devices can help track long-term health trends.

Citing Multiple Sources in Vancouver Style

When you need to cite multiple sources at the same point, Vancouver style keeps things simple. Use commas to separate individual citations and a hyphen to show a continuous range of sources.

Use commas to separate different sources and hyphens for a continuous range

Example
Telemedicine adoption has accelerated across many healthcare systems (2, 4, 6–8).
– or –
Telemedicine adoption has accelerated across many healthcare systems.^{2, 4, 6-8}

Secondary References in Vancouver Style

Secondary referencing is used when you want to cite information that you found quoted or summarised in another source, but you cannot access the original material. In Vancouver style, you cite only the source you actually read, while mentioning the original author within your sentence.

Secondary referencing should be avoided when possible, and used only when the original work is truly unavailable.

Let’s say Patel’s 2023 article discusses a study by Green from 2015, and you could not access Green’s original work. Green (2015) does not appear in the reference list because you did not read the original study.

In-text citation:
Green’s 2015 findings on digital health adoption are summarised by Patel (4).
– or –
Green’s 2015 findings on digital health adoption are summarised by Patel.⁴

Reference list entry (only the source you read):
4. Patel R. Advancements in digital health systems. Journal of Medical Innovation. 2023;12(1):22–9.

Direct Quotes in Vancouver Style

Direct quotations must be placed inside double quotation marks. You may include the page number to show exactly where the quote was taken from.

Use p. for one page and pp. for multiple pages

Single page
“Remote consultations increase flexibility for both doctors and patients” (3, p. 12).
– or –
“Remote consultations increase flexibility for both doctors and patients.”³(p. 12)

Multiple pages
“Remote consultations increase flexibility for both doctors and patients”(3, pp. 12–13).
– or –
“Remote consultations increase flexibility for both doctors and patients.”³(pp. 12–13)

Citing AI Tools like ChatGPT in Vancouver Style

Vancouver style does not have official guidelines for generative AI tools yet, but most universities treat AI-generated text as personal communication, since the content cannot be retrieved by others. When discussing the tool itself, however, you may cite it as an online source.

Citing ChatGPT Output (Personal Communication)

In-text citation:
When prompted with “Explain how AI assists in telemedicine,” ChatGPT generated a summary of current digital tools (personal communication).

Reference list entry:
Because the conversation cannot be accessed by readers, no reference list entry is provided.

Citing ChatGPT as a Tool (Online Source)

In-text citation:
Large language models such as ChatGPT are increasingly used in clinical research (10).
– or –
Large language models such as ChatGPT are increasingly used in clinical research.¹⁰

Reference list entry:
10. OpenAI. ChatGPT [Internet]. 2025. Available from: https://chat.openai.com/

⚠️ Important Note on Citing AI Tools

Guidelines for citing AI tools like ChatGPT vary widely between universities, and many institutions are still updating their policies. Always check your department’s or university’s official referencing guide to ensure you follow the correct requirements.

Reference List (Vancouver Style)

Your reference list appears at the end of your document and should:

• Include every source cited in the text
• Be numbered in the order of appearance (not alphabetically)
• Follow strict punctuation rules

For a clearer understanding of how different sources should be formatted, here are sample Vancouver references for common source types. For further information, read this blog.

References Formatted in Vancouver Style

Journal article
Kim J, Patel R. The impact of wearable sensors on chronic disease management. Digital Health Journal. 2022;18(2):101–9.

Book
Lopez S. Telemedicine in Modern Healthcare. London: MedTech Press; 2021.

Website
HealthTech Insights. How AI is improving patient triage. 2023. Available from: https://www.healthtechinsights.org/triage

Conference paper
Wong L, Carter M. Integrating mobile diagnostics into emergency services. In: Proceedings of the International Medical Technology Conference; 2021 Oct 10–12; Berlin, Germany. p. 55–60.

Thesis / Dissertation
Rahman M. Adaptive learning algorithms for digital tutoring systems [PhD dissertation]. Manchester: University of Manchester; 2023.

Report
International Health Board. Global Telehealth Outlook 2023. Geneva: IHB Publications; 2023.

YouTube Video
MedTech Channel. How digital tools support patient care [Internet]. YouTube; 2024 Feb 10. Available from: https://www.youtube.com/watch?v=example123

Dataset
HealthData Lab. Patient activity records 2019–2023 [dataset]. London: HealthData Repository; 2023. Available from: https://www.healthdata.org/patient-activity

Legislation
United Kingdom. Digital Health Act 2021, c.15.

Summary

Vancouver referencing may look detailed at first, but once you understand the numbering system, it becomes much easier to apply consistently. Simply assign each source a number in the order you cite it and keep that number throughout the text. For more help with academic writing, check out our blogs on citation techniques, quoting, paraphrasing, and plagiarism.