Vancouver system

Source: Wikipedia, the free encyclopedia.

The Vancouver system, also known as Vancouver reference style or the author–number system, is a

author–date, or "Harvard", system.[1][2] Vancouver style is used by MEDLINE and PubMed.[3]

Hundreds of

Helsinki Declaration, and research projects must be recommended by an independent ethics committee.[5]

In the broad sense, the Vancouver system refers to any author–number system regardless of the formatting details. A narrower definition of the Vancouver system refers to a specific author–number format specified by the

ICMJE Recommendations (Uniform Requirements for Manuscripts, URM). For example, the AMA reference style
is Vancouver style in the broad sense because it is an author–number system that conforms to the URM, but not in the narrow sense because its formatting differs in some minor details from the NLM/PubMed style (such as what is italicized and whether the citation numbers are bracketed).


Author–number systems have existed for over a century and throughout that time have been one of the main types of

Uniform Requirements for Manuscripts Submitted to Biomedical Journals
(URMs). Part of the URMs is the reference style, for which the ICMJE selected the long-established author–number principle.

The URMs were developed 15 years before the

JAMA version[9]
when reprinting the Uniform Requirements.

In the early 2000s, with the Web having become a major force in academic life, the idea gradually took hold that the logical home for the latest edition of the URMs would be the ICMJE website itself (as opposed to whichever journal article or supplement had most recently published an update). For example, as of 2004, the editors of Haematologica decided simply to invite their authors to visit for the 2003 revision of the Uniform Requirements.[10]

Since the early to mid-2000s, the United States National Library of Medicine (which runs MEDLINE and PubMed) has hosted the ICMJE's "Sample References" pages.[2] Around 2007, the NLM created Citing Medicine, its style guide for citation style, as a new home for the style's details. The ICMJE Recommendations now point to Citing Medicine as the home for the formatting details of Vancouver style.[4] For example, in the December 2013 edition of the ICMJE Recommendations, the relevant paragraph is IV.A.3.g.ii. (References > Style and Format).[4]

Sample usage

Labelling citations

References are numbered consecutively in order of appearance in the text – they are identified by

1, or a combination[1]. The number usually appears at the end of the material it supports, and an entry in the reference list would give full bibliographical information for the source:

Blood loss and the number of patients requiring post-operative blood transfusions were significantly greater, but operation and fluoroscopy times were significantly shorter, for the DHS versus the PFNA group[1].

And the entry in the reference list would be:

  1. Xu YZ, Geng DC, Mao HQ, Zhu XS, Yang HL (2010). "A comparison of the proximal femoral nail antirotation device and dynamic hip screw in the treatment of unstable pertrochanteric fracture". The Journal of International Medical Research. 38 (4): 1266–1275.
    S2CID 20812098

Placing citations

Several descriptions of the Vancouver system say that the number can be placed outside the text punctuation to avoid disruption to the flow of the text, or be placed inside the text punctuation, and that there are different cultures in different traditions.

Chicago Style Manual.)[15] The original Vancouver system documents (the ICMJE recommendations
and Uniform Requirements for Manuscripts Submitted to Biomedical Journals) do not discuss placement of the citation mark.

Format of citations

Different formats exist for different types of sources, e.g. books, journal articles, etc.

Format of names

Formatting for all names (e.g., authors, editors, etc.) is the same.

General rules for names:[16]

  • List names in the order they appear in the text
  • Enter surname (family or last name) first for each author
  • Capitalize surnames and enter spaces within surnames as they appear in the document cited on the assumption that the author approved the form used. For example: Van Der Horn or van der Horn; De Wolf or de Wolf or DeWolf.
  • Convert given (first) names and middle names to initials, for a maximum of two initials following each surname
  • Give all authors, regardless of the number
  • Separate author names from each other by a comma and a space
  • End author information with a period
  • See exceptions for author in Appendix F: Notes for Citing MEDLINE/PubMed.

Although Citing Medicine does not explicitly mandate merging initials (e.g. "R. K." would be merged into "RK"), the examples used throughout the book do.

Journal articles

Standard journal articles
  • Leurs R, Church MK, Taglialatela M. H1-antihistamines: inverse agonism, anti-inflammatory actions and cardiac effects. Clin Exp Allergy. 2002 Apr;32(4):489–498.
  • Tashiro J, Yamaguchi S, Ishii T, Suzuki A, Kondo H, Morita Y, Hara K, Koyama I. Inferior oncological prognosis of surgery without oral chemotherapy for stage III colon cancer in clinical settings. World J Surg Oncol. 2014 May 10;12(1):145. [Epub ahead of print]

As an option, if a journal carries continuous pagination throughout a volume (as many medical journals do), the month and issue number may be omitted.

  • Thomas MC. Diuretics, ACE inhibitors and NSAIDs – the triple whammy. Med J Aust. 2000;172:184–185.


et al.
" (which most medical journals do not italicize):

  • Guilbert TW, Morgan WJ, Zeiger RS, Mauger DT, Boehmer SJ, Szefler SJ, et al. Long-term inhaled corticosteroids in preschool children at high risk for asthma. N Engl J Med. 2006 May 11;354(19):1985–1997.

Optionally, a unique identifier (such as the article's DOI or PMID) may be added to the citation:

  • von Itzstein M, Wu WY, Kok GB, Pegg MS, Dyason JC, Jin B, et al. Rational design of potent sialidase-based inhibitors of influenza virus replication. Nature. 1993 Jun 3;363(6428):418–423.
    PMID 8502295

NLM elides ending page numbers and uses a hyphen as the range indicating character (184-5).[17] Some journals do likewise, whereas others expand the ending page numbers in full (184–185), use an en dash instead of a hyphen (184–5), or both (184–185).

Virtually all medical journal articles are published online. Many are published online only, and many others are published online

AMA style
puts "[published online Month Day, Year]" at the end of the article title. It no longer uses the term "Epub" and no longer includes the words "ahead of print". It omits the year from its normal location after the journal title abbreviation if there is no print data to give (online-only publication).

The titles of journals are abbreviated. There are no periods in the abbreviation. A period comes after the abbreviation, delimiting it from the next field. The abbreviations are standardized. The standardization was formerly incomplete and internal to organizations such as NLM. It is now formalized at the


Articles not in English

As per journal articles in English:

  • Forneau E, Bovet D. Recherches sur l'action sympathicolytique d'un nouveau dérivé du dioxane. Arch Int Pharmacodyn. 1933;46:178–191. French.


adds an English translation of the title enclosed in square brackets right after the title. The language is specified in full after the location (pagination), followed by a period.


Surname Initial(s). Book title. Edition – if available: Publisher, place of publication; Year.

Personal author(s)
  • Rang HP, Dale MM, Ritter JM, Moore PK. Pharmacology. 5th ed. Edinburgh: Churchill Livingstone; 2003.
Editor(s) or compiler(s) as authors
  • Beers MH, Porter RS, Jones TV, Kaplan JL, Berkwits M, editors. The Merck manual of diagnosis and therapy. 18th ed. Whitehouse Station (NJ): Merck Research Laboratories; 2006.
Authored chapter in edited publication
  • Glennon RA, Dukat M. Serotonin receptors and drugs affecting serotonergic neurotransmission. In: Williams DA, Lemke TL, editors. Foye's principles of medicinal chemistry. 5th ed. Philadelphia: Lippincott Williams & Wilkins; 2002.

Electronic material

  • World Health Organization (WHO). Mortality country fact sheet 2006 [internet]. Geneva: WHO; 2006. Available from:


  1. ^ "Reference styles". British Medical Association (BMA). Archived from the original on 5 October 2016. Retrieved 2016-10-04.
  2. ^ a b International Committee of Medical Journal Editors (ICMJE) . "Uniform Requirements for Manuscripts Submitted to Biomedical Journals: Sample References". United States National Library of Medicine. Retrieved 2013-03-01.
  3. ^ Patrias K (2007). Wendling D (ed.). Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers. Bethesda, Maryland, US: United States National Library of Medicine.
  4. ^ a b c "Recommendations for the Conduct, Reporting, Editing, and Publication of Scholarly Work in Medical Journals" (PDF). International Committee of Medical Journal Editors (ICMJE).
  5. ^ "Legal statutes and guidelines: the Vancouver recommendations".
  6. PMID 2001512
  7. .
  8. .
  9. .
  10. .
  11. ^ "Vancouver (Numbered) System". University of Leicester. Archived from the original on 27 March 2015.
  12. ISSN 0972-5687. Archived from the original
    (PDF) on 6 April 2018.
  13. ^ "Vancouver Citation Style" (PDF). Vancouver Community College. Archived from the original (PDF) on 2015-02-09. Retrieved 2015-01-05. The citation in brackets is placed after any commas and periods, and before any colons and semi-colons
  14. ^ "MLA Citation Style". Cornell University Library. Archived from the original on 2 February 2016.
  15. ^ a b "IEEE Citation Reference" (PDF). IEEE. Archived from the original (PDF) on 2011-04-08. Retrieved 2011-05-12. References ... appear on the line, in square brackets, inside the punctuation.
  16. ^ Patrias K (2007). "Journals". In Wendling D (ed.). Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet] (2nd ed.). Bethesda, MD: National Library of Medicine (US). Retrieved 2019-03-31.
  17. ^ Patrias K (2007, rev. 2015), Wendling D (tech. ed.), Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers, Bethesda (MD): United States National Library of Medicine; p. 41 (PDF), chap. 1, p. 8 (PubReader).
  18. ^ Patrias K (2007). "Appendix A: Abbreviations for Commonly Used English Words in Journal Titles". In Wendling D (ed.). Citing Medicine: The NLM Style Guide for Authors, Editors, and Publishers [Internet] (2nd ed.). Bethesda (MD): National Library of Medicine (US).
  19. ^ "List of Title Word Abbreviations (LTWA)".

External links

Many medical institutions maintain their own style guides, with information on how to cite sources: