Vancouver referencing system

Why is it important to reference publications you cite in your essay or project?

Referencing your work correctly is essential. If you acknowledge the work of others you are taking steps to prevent plagiarising someone else's work. You are also allowing the reader to trace your line of research. You need to give sufficient detail of the item to which you are referring so that readers can easily trace the item whether it be a book chapter, article or webpage.

When gathering information for your assignment from books, journals and webpages it is important that you keep a record of where your information comes from. This can be done using bibliographic referencing software such as Reference Manager. It is difficult and very time consuming to try and trace a book with just a chapter heading and an idea of how big the book might by by the size of you copied pages and a vague idea that you got it from the library... or a friend!

The Vancouver referencing system

The School of Medicine recommends that all BM students use the Vancouver style of referencing - this is the style used in most leading medical journals. There are detailed guidelines on how to implement Vancouver referencing - however different journals have subtley different formats for their references.

Therefore, for the sake of consistency, the School of Medicine recommends that you follow the style of Vancouver referencing used by the BMJ.

Citing references in your text (in-text citation), in the Vancouver/BMJ style

You should use superscript Arabic numerals e.g. 2 for in-text citations; the superscript number links directly to the reference list at the end of the piece of work e.g.:

...When quoting scientific research, authors should cite references and avoid reliance on abstracts.1 Some authors who haven't published recent research like to write review articles which are not peer reviewed so they can cite many of their own previous publications...

Doing superscript numbers in Word

Since Word is the word processor that most students are likely to use, it's worth mentioning how you can insert superscript numbers.

  1. Type the number, as normal, in the correct position in your text.
  2. Carefully select the number by itself.
  3. From Word's menu bar select: Format > Font
  4. In the list of options in the pop-up panel, mark "Superscript", then click on "OK".


Reference numbers should go:

  • After commas and full stops.
  • Before colons and semicolons.

Assigning a reference number

Reference numbers should be assigned in the order in which the references first appear in your text. If you cite the same reference twice, re-use its original reference number - there is no need to give it a new one.

The following is from an editorial in the BMJ (A European alcohol strategy [editorial]. BMJ 2006;333:871-2) - it has been abridged for the purposes of this example:

"The industry has also used the single market to justify attacks on labels being introduced in France to warn pregnant women of the hazards of drinking.4 Consequently, national health ministries ... asked the commission to prepare a comprehensive strategy to reduce alcohol related harm.5

"...The resulting report catalogued the adverse effects on health in detail and showed how alcohol attributable disease, injury, and violence cost the health, welfare, employment, and criminal justice sectors £84bn (€125bn; $157bn) each year, including £40bn in lost production, while the intangible costs of suffering and lost life added a further £182bn each year.6

"The draft strategy that emerged is now being considered by all the commissioners and a decision on whether to adopt it is expected at the end of October...

"The strategy foresees several actions at the European level... However, its main thrust will be to support collaboration among member states, encouraging them to implement policies that are evidence based and proportionate.

"Given the magnitude of the threat to health posed by hazardous drinking, some may argue that the strategy should go much further.5"

Citing specific pages

To cite a specific page, indicate the page number in brackets after the reference number:

...there is strong evidence of benefit in elderly patients, 12 (p11) ...

To cite more than one page, indicate the page range:

...there is strong evidence of benefit in elderly patients, 12 (pp11-12) ...

Citing several references at the same time

To cite two references at one, include both reference numbers:

...there is strong evidence of benefit in elderly patients, 12 13 ...

To simultaneously cite more than two, consecutive references at once, just indicate the range:

...there is strong evidence of benefit in elderly patients, 12-14 ... If you are citing a mixture of consecutive and non-consecutive references, then indicate specific references and ranges as appropriate: ...there is strong evidence of benefit in elderly patients, 10 12-14 ...

Reference list at end of your paper (end-text citation)

References should be numbered consecutively in the order in which they are first mentioned in the text; they should not be listed alphabetically by author or title or put in date order.
  1. Vickers A. Guidelines for authors of books and papers on complementary medicine. Complement Ther Med 1999;7:245-9.
  2. Caveman A. The invited review? or, my field, from my standpoint, written by me using only my data and my ideas and citing only my publications. J Cell Sci 2000;113:3125-6.
References cited only in tables or figure legends should be numbered in accordance with the sequence established by the first identification in the text of the particular table or figure.

Secondary references

Occasionally you will read a journal article that refers to another document containing the information you need to cite... but you are unable to obtain this second source. If this is the case, do not reference the second source as if you had read it. You have not, and you must make it clear that you have not. Instead, use the following format: [Reference for the 2nd source] In: [Reference for the 1st source]


...there is strong evidence of benefit in elderly patients, 12 ...


  1. Johnson VA, Brun-Vezinet F, Clotet B, Conway B, Kurizkes DR, Pillay D, et al. Update of the drug resisance mutations in HIV-1: Fall 2005. Top HIV Med 2005;13:125-31. In: Deeks SG. Antiretroviral treatment of HIV infected adults. BMJ 2006;332:1489-93.

Notes for referencing journal articles

Journal names

The titles of journals should be abbreviated according to the style used in Medline. Consult the List of Journals Indexed in Index Medicus (Medline), held in the library or check citation on Medline. List the first six authors followed by et al.

Part and issue numbers

Most journals carry continuous pagination throughout a volume - so part and issue numbers can be omitted. Add part and issue numbers only when required.

Where to find the necessary information for a book reference

Most of the information you will need will (usually) be on the front and back of the title page, just inside the book. If you can not find it there, then look up the book on WebCat and view the "Full catalogue details" tab.
  • Pay careful attention to the punctuation within the reference.
  • With books, look for the original publication date of the relevant edition. If a book has been reprinted, the reprint dates do not count.

Notes about citing authors

  • If there are more than six authors, list the first six followed by "et al."
  • A "van" or "de" name in the end-text citation will always take the form of "van Schayck CP", not "Schayck CP van".
  • A "van" or "de" name takes caps if the author gives it caps - and definitely has caps if it is the first author for the reference.

Citing websites

Referencing any resource on the web has the added complication that it may change - it could be moved, updated or deleted at any time. Therefore, in addition to the standard reference information, you need to also include details of the web address (URL) and the date that you last check the page/website/resource. When quoting the URL, you may leave off the "http://" - if the address starts with "www..." (or something similar). For a URL such as then it's better to keep the "http://" in place.

If you don't have information for a complete reference

Not all documents (particularly web pages and pamphlets) have the necessary information on them for you to write a complete reference. If this is the case, put down whatever information you have - remember that the reference should enable someone else to locate the document, so give them all the help you can.