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AMA 11th edition: A go-to guide

The style of JAMA and most US medical journals. How AMA 11 handles superscript citations, its specific reference list conventions, and the broader editorial rules of medical writing in the US.

11 min readLast updated May 2026

AMA style is the dominant style of US medical publishing. JAMA, the JAMA Network specialty journals, and many other major US clinical journals follow it. If your target publication is American medicine, you are almost certainly writing in AMA.

The canonical reference is the AMA Manual of Style: A Guide for Authors and Editors, 11th Edition, published by Oxford University Press for the American Medical Association in 2020. AMA also maintains the AMA Manual of Style online at amamanualofstyle.com, which carries updates and clarifications between print editions. This blog post is an orientation. It is not a rulebook and does not replace the Manual when you need the canonical answer to a specific question.

Where AMA came from and who uses it

The American Medical Association is the largest professional society of physicians in the United States. It has published its style manual in various forms since 1962, refining the conventions over more than half a century. The 11th edition, released in 2020, is the current one. It is broader than just citation style: the Manual covers grammar, medical terminology, statistics, units of measurement, ethical and legal issues in medical publishing, and the production conventions of medical journals.

Disciplines that use AMA include the full range of clinical and biomedical specialties published in American medical journals: cardiology, oncology, surgery, internal medicine, paediatrics, psychiatry, neurology, public health, and dozens of subspecialties whose primary journals are AMA-affiliated. Some adjacent fields (pharmacy, dentistry, veterinary medicine) use AMA in journals that have adopted it but more often use other styles. Always check the target journal’s author instructions.

The mechanics: spelling, punctuation, and usage

AMA inherits American English conventions and is precise about medical terminology, units of measurement, statistical reporting, and the structure of clinical writing. The Manual’s coverage of statistical and methodological conventions is unusually comprehensive among style guides.

Spelling

American spelling is the default. For medical terms with multiple accepted spellings, AMA prefers the modern medical-dictionary spelling. Stedman’s Medical Dictionary and Dorland’s Illustrated Medical Dictionary are the conventional references when the Manual itself does not give explicit guidance.

Punctuation

American punctuation. Commas and periods sit inside closing quotation marks. The serial comma is used in lists of three or more items. AMA is precise about specific punctuation conventions in clinical writing: hyphens in chemical names, en dashes in number ranges, the colon convention in ratios, and the comma convention in large numbers.

Numbers and units

Medical writing is dense with numbers, and AMA reflects that. Most numbers in scientific contexts appear as figures, including small whole numbers when they refer to measurements, doses, sample sizes, or statistical quantities. SI units are preferred for laboratory values, with traditional units (such as mg/dL for glucose) accepted in clinical contexts where they remain the working convention. Statistical reporting follows specific AMA conventions: P values, confidence intervals, and effect sizes have settled forms in the Manual.

Capitalisation and italics

Article titles in references use sentence case (first word, first word after a colon, and proper nouns only). Journal title abbreviations follow the NLM standard list and are not italicized in AMA reference list entries. Book titles use title case and are italicized in references. Latin abbreviations such as et al. follow the Manual’s typographic convention; consult the current edition for the specific styling.

The citation system, at a glance

AMA uses a numeric citation system with superscript numerals. Each cited source is assigned a number in the order it is first cited in the text, and that number appears as a superscript at the relevant point in the running prose. The full bibliographic information for each numbered source appears in the reference list at the end of the paper, in numeric order matching the citation sequence.

Citation numbers carry no author or year in the running text. The superscript number does the work, and the reader looks up the full detail in the reference list. AMA and Vancouver share this overall architecture; the differences are in the punctuation and element ordering of reference list entries.

In-text citations

Superscript numerals sit at the relevant point in the running text. They appear after the cited statement, generally after most punctuation marks, including commas, periods, and closing quotation marks. They sit before colons and semicolons. The Manual covers the precise placement rules in detail.

Examples to internalize

Four in-text citations following AMA conventions. Sources are invented for illustration. Superscript numbers are shown as small raised numerals.

  • Single citation at the end of a sentence: Patients with the condition show elevated markers.3
  • Multiple citations in sequence: Several recent studies converge on this finding.3,7,11
  • Continuous citation range: Earlier work in the area is extensive.3-7
  • Citation incorporated into the sentence: As Okonkwo and colleagues3 demonstrated, the convergence is observable across cohorts.

The reference list

The reference list starts on a new page after the body of the paper with the heading References at the top. Entries are numbered in the order they first appear in the text, formatted with a hanging indent. Each entry begins with its citation number followed by a period (not a bracket).

Each entry follows the four-part skeleton: who, when, what, where, with AMA-specific element forms. Author lists use surname followed by initials (no periods between initials, no comma inside the name). Up to six authors are listed in full; for seven or more, AMA lists the first three followed by et al. This three-author cutoff is one of the differences from Vancouver, which uses six.

Examples to internalize

Four sample reference list entries. All authors and titles are invented.

  • Journal article: 1. Okonkwo AC, Patel R, Stein M. Convergence properties of biomarker estimators across cohorts. J Clin Inq. 2022;14(2):121-144.
  • Book: 2. Stein M. Quiet Revisions: Editing as a Craft. Bracewell Press; 2019.
  • Chapter in an edited book: 3. Choi J. On voice. In: Stein M, ed. The Shape of Scholarly Prose. Bracewell Press; 2021:88-112.
  • Online article: 4. Patel R. Form and feeling in recent criticism. Mod Lett Rev. Published March 14, 2022. Accessed April 1, 2022. https://example.org/mlr/12345

Things to remember about the reference list

  • Numeric order matching the order of first citation. Not alphabetical.
  • Number followed by a period at the start of each entry, not a bracket.
  • Author surname followed by initials without periods between initials and without commas inside the name itself.
  • Up to six authors listed in full; seven or more, the first three and then et al.
  • Sentence case for article and chapter titles, with no quotation marks.
  • NLM-standard journal abbreviations, no italic.
  • Year, semicolon, volume, parenthesized issue, colon, page range. The pattern is consistent and worth internalizing.
  • Accessed-date required for online sources.

Footnotes in AMA

AMA does not use footnotes for citation. Citations stay in the superscript numeric system, and the reference list carries the bibliographic detail. Footnotes appear in tables and figures (where they explain symbols, abbreviations, or specific table cells), in author affiliations on the title page, and occasionally as content notes in editorial pieces. Most AMA journals discourage footnotes in research papers, preferring all explanatory material integrated into the text or moved to tables.

What RightMyWork does with AMA 11

When you pick AMA on the upload screen, the editor applies AMA 11 conventions across your document. In-text citations are checked for the superscript-numeral format and placement. Reference list entries are reviewed for the AMA author-name format (surname plus initials, no periods, three-author cutoff for et al.), NLM-standard journal abbreviations, sentence-case article titles, and the year-semicolon-volume-issue-page punctuation pattern. Citation numbering against text-appearance order is checked.

Every change lands as a tracked change in Word. Citations that point to numbers without matching reference list entries are flagged. Reference list entries that are never cited are flagged. Where the editor cannot confidently apply a rule (an unusual source type, an unfamiliar abbreviation, a regional convention), it surfaces a query rather than rewriting silently.

Where to go from here

For the rules in their canonical form, the AMA Manual of Style online is the actively maintained resource, and the printed 11th edition is the definitive reference. Both are produced by the people who define the style for AMA publications. The NLM Catalog remains the authoritative source for journal title abbreviations.

When you are ready to apply AMA 11 to your draft, the upload form on the homepage is one click away. The first 3,000 words on a new account are free.

Questions and answers

Quick answers

How is AMA different from Vancouver?

Both are numeric citation systems for medical writing, and the two have converged on many conventions, but the detailed reference list forms differ in small visible ways: author-name punctuation, the position of certain elements, the exact handling of online sources. AMA is the in-house style of the American Medical Association and its journals; Vancouver is the ICMJE family. If your target is JAMA or another AMA-affiliated journal, use AMA. If your target is a general clinical journal indexed in MEDLINE, Vancouver typically fits.

Where is the canonical AMA reference?

The AMA Manual of Style: A Guide for Authors and Editors, 11th Edition, published by Oxford University Press for the American Medical Association in 2020. The AMA Manual of Style is also available online at amamanualofstyle.com, which is the actively maintained resource that includes updates between print editions. This blog post is an orientation; the Manual is the canonical source.

Are citations superscript or bracketed?

AMA uses superscript numerals for in-text citations, not bracketed or parenthetical forms. The superscript number sits at the relevant point in the running text, after the cited statement and after most punctuation. This is one of the immediately visible differences between AMA and the bracketed numeric systems of IEEE or some Vancouver-format journals.

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