AMA citation style (11th edition): a complete guide with examples

AMA style is the citation system of the AMA Manual of Style, the house guide of JAMA and the JAMA Network, and a required style across much of medicine, public health, pharmacy, and nursing. The current edition is the 11th, published in 2020. In the text, citations are superscript numbers; the reference list is numbered to match.

AMA sits close to Vancouver, and the two are often confused: both are numeric, both abbreviate journal titles the NLM way, and both write authors as surname plus unpunctuated initials. The differences live in the details: where superscripts sit relative to punctuation, the et al threshold, how page ranges are printed, and how DOIs are written.

This guide covers the superscript rules, the reference formats for the main source types, worked examples, the errors that cost marks, and how to generate AMA references automatically.

Who uses AMA style and what the 11th edition changed

If your programme or target journal follows the JAMA Network or names the AMA Manual of Style, this is your system. Medical schools and health-science programmes in the United States are the heaviest users, and many pharmacy and nursing departments require it for capstones and theses.

Two 11th edition changes still trip up writers trained on older guides. First, the place of publication is no longer included in book references: publisher and year now stand alone. Second, DOIs are written as doi:10.xxxx, lowercase with no space after the colon. If a template you found online shows a city before the publisher or 'DOI:' in capitals with a space, it predates 2020 and will read as dated to anyone marking against the current manual.

If your school's guide is older than 2020, ask which edition it targets before you standardise. Writing to the 11th while being marked against the 10th, or the reverse, produces a document that is consistently wrong in one direction; annoying, but at least fixable in a single pass once you know.

AMA in-text citations: superscript number rules

Citations are superscript Arabic numerals, assigned in order of first appearance, and AMA is precise about where they sit relative to punctuation. The examples below show the numbers inline; in your document they are superscript. A few programmes allow parenthetical numbers where superscript is impractical; if yours does, keep one form throughout.

The placement rules:

• Superscripts go outside periods and commas: 'as reported in two early trials.1,2'
• Superscripts go inside colons and semicolons: 'two mechanisms have been proposed3: inflammation and fibrosis.'
• Separate multiple citations with commas and no spaces: 1,3,5.
• Compress consecutive numbers into a hyphenated range: 4-7.
• Reuse the original number for every repeat citation of the same source.
• If you name authors in the sentence, keep the superscript: 'Chen et al2 reported a smaller effect.'

The AMA reference list: core rules

Entries are numbered to match the order of first citation, never alphabetised. Author and journal conventions resemble Vancouver's, with a handful of AMA-specific details that markers check. One rule surprises almost everyone: sources cited only in a table or figure legend are numbered according to where that table or figure is first mentioned in the text, so moving a figure during revision can renumber your references.

What every entry follows:

• Authors: surname plus initials, no periods: Chen L, Okafor P.
• One to six authors: list them all. Seven or more: first three, then et al.
• Article titles in sentence case; journal names italic and abbreviated per the NLM: JAMA, N Engl J Med.
• Year;volume(issue):pages, with full closing page numbers: 2020;323(15):1499-1500.
• DOIs appended as doi:10.xxxx with no space after the colon and no period after the DOI.
• No place of publication in book references.

AMA vs Vancouver: the differences that matter

Because the two styles share NLM journal abbreviations and unpunctuated author initials, whole theses get written in an accidental hybrid of both. If you trained on Vancouver, audit for the points below specifically; people who read JAMA all day spot a Vancouver page range instantly.

Where they split:

• In-text form: AMA specifies superscript; Vancouver guides accept superscript, parentheses, or brackets depending on the school.
• Placement: AMA fixes superscripts outside periods and commas, inside colons and semicolons.
• Author threshold: AMA lists one to six in full and cuts to the first three plus et al at seven; Vancouver lists the first six, then et al.
• Page ranges: AMA prints closing pages in full (1499-1500); Vancouver elides (1499-500).
• DOIs: AMA writes doi:10.xxxx with no space after the colon.
• Books: AMA dropped the place of publication in the 11th edition; Vancouver keeps it.

Journal articles in AMA style

The template: Author AA, Author BB. Title of the article in sentence case. Abbrev J Title. Year;volume(issue):pages. doi:10.xxxx

A made-up example with every element in place: Chen L, Okafor P. Beta-blockade after myocardial infarction in older adults. JAMA Cardiol. 2024;9(4):310-318. doi:10.1000/xyz123

And one with more than six authors, showing the first-three rule: Osei R, Haddad N, Virtanen A, et al. A core outcome set for community hypertension trials. JAMA. 2023;330(18):1742-1751. Note the full closing page numbers in both examples; AMA does not elide 1742-1751 to 1742-51, which is exactly the kind of Vancouver habit that leaks into AMA manuscripts. If a journal uses article numbers rather than pages, cite the article number in the same slot. The fastest visual check that an entry is AMA-shaped: a sentence-case article title against an italic, abbreviated journal name, with no period after a trailing DOI.

Books and chapters in AMA style

A book: Author AA. Title of the Book in Title Case. 3rd ed. Publisher; 2021. Notice what is missing: no city, no state. Book titles are italic and in title case, unlike article titles, and the edition statement sits between title and publisher. Editions appear from the 2nd onward; a first edition carries no edition statement.

A chapter in an edited book: Author AA. Chapter title in sentence case. In: Editor BB, ed. Title of the Book. Publisher; 2021:45-62. The chapter's page range follows the year after a colon, and the editor takes 'ed.' (or 'eds' for several) after the name. A whole edited book cites the editors up front: Editor BB, ed. Title of the Book. Publisher; 2020.

Websites, guidelines, and preprints in AMA style

A webpage: Author or Organisation. Title of the page. Name of the website. Published date if given. Accessed date. Full page address. AMA wants the accessed date because pages change, and it sits before the address, not after it. If no author is named, start the entry with the title; if there is no published date, the accessed date alone carries the load.

Clinical guidelines are cited like reports, with the issuing body as author. Preprints must be labelled as such: Author AA. Title of the preprint. Preprint posted online March 5, 2024. medRxiv. doi:10.1000/xyz123. Flag preprint status honestly; in a clinical thesis, presenting non-peer-reviewed work as published is the kind of error that surfaces in a defence, not just in marking. The label travels with the citation: if the preprint is later published, switch the entry to the journal version and re-check that it still supports your sentence.

Worked example: two sentences and their AMA references

Consider: 'Early beta-blocker trials reported a mortality benefit.1,2 Later pragmatic work questioned the effect in the reperfusion era3 and in older adults.1' The superscripts sit outside the periods, the cluster 1,2 has no space, and source 1 reuses its number on the second citation. Note also that source 3 binds to the clause about the reperfusion era, not to the end of the sentence; superscripts attach to the claim they support.

The matching reference list:

• 1. Chen L, Okafor P. Beta-blockade after myocardial infarction in older adults. JAMA Cardiol. 2024;9(4):310-318. doi:10.1000/xyz123
• 2. Alvarez M, Ito S. Early beta-blockade and 30-day mortality. Am Heart J. 2019;214(2):88-96.
• 3. Osei R, Haddad N, Virtanen A, et al. Beta-blockers in the reperfusion era. Eur Heart J. 2023;44(31):2901-2910.

Common AMA citation errors

The recurring ones, all cheap to avoid and expensive to leave in. Sweep for them once before submission and again after your final revision pass:

• Superscripts placed inside a period or comma; AMA puts them outside.
• Spaces inside citation clusters: 1, 3 instead of 1,3.
• Listing all eight authors instead of the first three plus et al.
• Eliding page ranges Vancouver-style (1499-500) where AMA prints them in full (1499-1500).
• Title case in article titles.
• Publisher cities copied from pre-2020 templates.
• 'DOI:' in capitals with a space, or a period added after the DOI string.
• Missing accessed dates on web sources.

Numbering is the part that breaks under revision

As with every numeric style, the dangerous failure is structural. Add one citation to your introduction during a late revision and every superscript after it shifts, along with the entire reference list. Chasing that by hand across a 200-page thesis is where mismatched numbers come from, and a mismatched number is worse than a formatting slip: it silently attributes a claim to the wrong source.

Treat numbering as something software derives from the text, not something you maintain. That single decision removes the whole class of error. The same applies to the list itself: after any structural change, regenerate it from the citation data rather than patching entries by hand.

Generate AMA citations automatically

The free AMA citation generator formats a reference from a DOI or paper details, with the NLM journal abbreviation and the doi: string in the right shape. If you have a bare DOI and want to inspect the record before citing it, run it through the free DOI lookup first.

In CiteDash, the Reference Manager stores each citation as a database object linked to a real paper. Superscript numbering and list order are derived from the text, so inserting a citation renumbers everything, and you can flip a whole thesis between AMA, Vancouver, and ten other styles without retyping a single entry. Retracted papers are badged and blocked from citation before they can reach your reference list, which in clinical writing is not a nicety but a safeguard. The same citation objects flow into the compiled document, where the bibliography renders through citeproc in whichever style your school requires, so switching styles is a setting rather than a rewrite.