How do in-text citations work in AMA format?

AMA uses superscript Arabic numerals placed in the text at the point where the source is cited. Numbers are assigned in the order sources first appear — the first source cited becomes reference 1, the second becomes reference 2, and so on. If the same source is cited again later, use the same number it was originally assigned. The superscript number goes after punctuation (commas and periods) but before colons and semicolons.

How many authors do I list in an AMA reference?

List all authors if there are six or fewer. If there are seven or more authors, list the first three followed by 'et al.' This applies to the reference list entry. In the text, you only use the superscript number — author names never appear in AMA in-text citations.

AMA Citation Format

Q: What is AMA citation format?

AMA (American Medical Association) citation format is a referencing system used in medicine, nursing, health sciences, and related biomedical fields. It uses superscript numbers in the text — like this¹ — that correspond to a numbered reference list at the end of the document. References are numbered in the order they first appear in the text, not alphabetically. The current version is AMA 11th edition.

Q: How do I format a journal article in AMA style?

For a journal article in AMA 11th edition: Author AA, Author BB, Author CC. Title of article. Abbreviated Journal Name. Year;Volume(Issue):Page-Page. doi:10.xxxx/xxxxx. Author initials follow the last name with no periods between initials. Journal names are abbreviated using standard PubMed/NLM abbreviations. The year, volume, issue, and pages are formatted with specific punctuation — no spaces between year, semicolon, volume, parenthetical issue, colon, and page range.

Q: How do I cite a website in AMA format?

For a webpage in AMA format: Author AA. Title of page. Website Name. Published Month Day, Year. Updated Month Day, Year. Accessed Month Day, Year. URL. Include the published date if available, the updated date if the content has been revised, and always include the accessed date for web sources — this is required in AMA, unlike some other styles.

Q: What is the difference between AMA and APA citation?

AMA uses superscript numbers in the text and a numbered reference list ordered by first appearance. APA uses an author-date system — (Author, Year) — and an alphabetical reference list. AMA is standard in medicine and health sciences. APA is standard in psychology, education, and social sciences. The reference list formats, author name formats, journal abbreviation rules, and punctuation conventions are all different between the two styles.

AMA 11TH EDITION · SUPERSCRIPT NUMBERS · REFERENCE LIST · JOURNAL ABBREVIATIONS

Superscript Numbers, Reference Lists, and the Rules Medical Students Need to Know

How the AMA numbered citation system works, how to format in-text superscripts and reference list entries for journal articles, books, and websites, how to abbreviate journal names, when to use et al., and the errors that appear most often in health science papers.

18–22 min read Medicine, Nursing & Health Sciences AMA 11th Edition 3,900+ words

Custom University Papers Academic Writing Team

AMA citation guidance based on the AMA Manual of Style: A Guide for Authors and Editors, 11th edition (2020), published by Oxford University Press and maintained online at amamanualofstyle.com — the authoritative reference for all AMA formatting rules.

If you are studying medicine, nursing, public health, dentistry, or any allied health field, AMA citation format is what your department expects. It looks different from APA or Harvard — no author names in the text, no parenthetical years, just a small superscript number that points to a numbered list at the end of the document. The format keeps medical writing clean and fast to read. But the reference list itself has very specific rules — abbreviated journal names, exact punctuation sequences, author initials with no periods — and getting those details wrong matters. This guide covers the system, the rules, and the errors to avoid.

AMA 11th Edition Superscript Numbers Reference List Format Journal Articles Books & Chapters Websites & Online Sources Journal Abbreviations Author Name Format Et Al. Rules DOIs & URLs AMA vs APA Common Errors

What This Guide Covers

How AMA Works: The Numbered System In-Text Superscript Citations Reference List: Structure and Rules Citing Journal Articles Citing Books and Book Chapters Citing Websites and Online Sources Other Common Source Types Author Name Format Journal Name Abbreviations DOIs and URLs in AMA AMA vs APA vs Vancouver Common Errors That Cost Marks Frequently Asked Questions

How AMA Works: The Numbered System

AMA uses a citation-sequence system. Every source gets a number. That number first appears in the text as a superscript the moment you cite the source. The same number then appears in the reference list at the end of the document, with the full citation details.

The key difference from APA or Harvard: numbers run in the order sources are first mentioned — not alphabetically. The first source you cite becomes reference 1. The next new source becomes reference 2. If you cite source 1 again twenty pages later, you still use superscript 1. The numbers never change once assigned.

In-Text: Superscript Number

A small raised number appears in the text at the point of citation — after punctuation in most cases. No author name. No year. Just the number. Clean and minimal, which is why medical journals prefer it.

Reference List: Numbered in Order

The reference list is numbered sequentially — 1, 2, 3 — in the order sources first appeared in the text. Not alphabetical. Each number corresponds to exactly one superscript in the text.

The Official Source

The authoritative guide is the AMA Manual of Style, 11th edition (2020), published by Oxford University Press. The online version is maintained at amamanualofstyle.com. Your institution may require library access.

Who Uses AMA Format?

AMA is the standard citation style for the Journal of the American Medical Association (JAMA) and most major medical journals. It is required for student papers in many medical schools, schools of public health, nursing programmes, pharmacy, and dentistry programmes. If your assignment brief says “AMA style” or references the AMA Manual of Style, this is the system. If it says “Vancouver,” note that Vancouver and AMA are closely related — both use numbered citations — but they have formatting differences, particularly in punctuation and journal name handling.

In-Text Superscript Citations

The in-text citation in AMA is a superscript Arabic numeral. No brackets, no author name, no year. Just a raised number after the relevant word or sentence.

Placement Rule 1 — After Punctuation (Commas and Periods)

Superscript Goes After Commas and Periods

When the citation falls at the end of a clause or sentence, the superscript number goes after the comma or period, not before it. This is the opposite of how footnote numbers work in some other styles.

Correct: Hypertension is a major risk factor for cardiovascular disease.¹ | Incorrect: Hypertension is a major risk factor for cardiovascular disease¹.

Placement Rule 2 — Before Colons and Semicolons

Superscript Goes Before Colons and Semicolons

When a citation falls just before a colon or semicolon, place the superscript before those punctuation marks — not after. This is the one exception to the “after punctuation” rule.

Correct: Three studies confirmed the finding²: a 2019 RCT, a 2021 cohort study, and a 2022 meta-analysis.

Placement Rule 3 — Citing Multiple Sources at Once

Multiple Superscripts in One Place

When citing more than one source at the same point, list the superscript numbers in sequence, separated by commas (no spaces), or use a hyphen for a consecutive range. All within a single superscript tag.

Comma-separated: Several trials have demonstrated this effect.^3,5,7 | Range: Meta-analyses consistently support this conclusion.^4-6

Placement Rule 4 — Citing the Same Source Again

Reuse the Original Number

When you cite a source you have already cited, use the same superscript number it was first assigned. Do not create a new number. The reference list entry for that source appears only once, at its original number.

Example: If Smith et al. was first cited as reference 3, every subsequent citation of that paper throughout the document also uses superscript 3.

Author Names Never Appear in AMA In-Text Citations

Students switching from APA often write “(Smith et al., 2021)” by habit. In AMA, that is wrong. There are no parenthetical author-date citations. No author name, no year, nothing in parentheses. The only in-text marker is the superscript number. If you find yourself writing an author name in the text for citation purposes, that is an APA habit — remove it and replace it with the superscript.

Reference List: Structure and Rules

The AMA reference list appears at the end of the document under the heading “References.” Entries are numbered sequentially and listed in the order they first appear in the text — not alphabetically. Every superscript in the text must have a corresponding entry in this list.

1Numbered in Order of First Appearance, Not Alphabetically

This is the defining feature of citation-sequence systems. Reference 1 is the first source you cited in the introduction. Reference 2 is the next new source. If you cite a source for the first time on page 8, it gets a later number regardless of the author’s last name. Do not sort alphabetically after writing — the order is set by where sources appear in the text.

2Author Last Name Then Initials, No Periods Between Initials

AMA author format: Last name followed by initials with no periods and no spaces between them. A comma separates multiple authors. Example: Smith AB, Jones CD, Lee EF. This is different from APA (Last, F. M.) and from Harvard. No periods after initials is one of the most common formatting errors students make when switching to AMA.

3Six or Fewer Authors: List All. Seven or More: First Three Then Et Al.

If a source has six or fewer authors, list all of them. If it has seven or more, list the first three authors followed by “et al.” — with a period after “al.” Note: this is the reference list rule. In the text, author names never appear at all in AMA, so et al. is only relevant for the reference list.

4Journal Names Are Abbreviated

AMA requires abbreviated journal names, not full titles. Use the standard NLM (National Library of Medicine) abbreviations — the same ones used in PubMed. Example: The New England Journal of Medicine becomes N Engl J Med. No periods in the abbreviation. If you cannot find an abbreviation, the NLM catalog at ncbi.nlm.nih.gov/nlmcatalog lists official abbreviations for every indexed journal.

5Specific Punctuation Pattern for Journal References

The punctuation sequence for a journal article reference is exact and unforgiving: Author(s). Title. Abbrev J Name. Year;Volume(Issue):StartPage-EndPage. doi:10.xxxx/xxxxx. Note the period after authors, period after title, period after journal name, then year immediately followed by semicolon, volume, issue in parentheses, colon, page range, period. No spaces before the semicolon, colon, or within the date-volume-page sequence.

Citing Journal Articles

Journal Article — Standard Format with DOI // Structure: Authors. Title. Abbrev Journal Name. Year;Volume(Issue):Pages. doi: 1. Langer EJ, Rodin J. The effects of choice and enhanced personal responsibility for the aged. J Pers Soc Psychol. 1976;34(2):191-198. doi:10.1037/0022-3514.34.2.191 // Author initials: no periods between them. Title: sentence case. Journal name: NLM abbreviation, italicised, period after it. Year then semicolon — no space. Volume then issue in parentheses. Colon then page range. doi: in lowercase, no space before the number.

Journal Article — Seven or More Authors (Et Al.) 2. Smith AB, Jones CD, Lee EF, et al. Long-term outcomes of early intervention in type 2 diabetes. Lancet. 2022;399(10330):1047-1058. doi:10.1016/S0140-6736(22)00024-1 // Seven or more authors: first three listed, then “et al.” with period. Et al. is not italicised in AMA reference lists.

Journal Article — No DOI, Found Online 3. Patel NR, Thompson KM. Vaccine hesitancy in primary care populations. Am Fam Physician. 2021;103(6):345-352. https://www.aafp.org/afp/2021/0315/p345.html // When no DOI is available and the article is online, include the direct URL. No “Retrieved from.” No access date required for stable journal content — only for pages that may change.

Journal Article — Print Only, No URL or DOI 4. Rosen G. The evolution of social medicine. In: Freeman HE, Levine S, Reeder LG, eds. Handbook of Medical Sociology. Prentice Hall; 1963:17-61. // For print-only sources with no digital identifier, end after the page range and period. No URL needed.

Where to Find NLM Journal Abbreviations

The NLM catalog at ncbi.nlm.nih.gov/nlmcatalog is the official source. Search by journal name and the record will list the NLM abbreviation. PubMed citations also display the abbreviation — if you found the article through PubMed, the abbreviated journal name is already shown in the citation. Many institutions also maintain local lists of common journal abbreviations for students. Do not guess at abbreviations — an incorrect abbreviation in a reference is a formatting error that affects reproducibility.

Citing Books and Book Chapters

Whole Book // Structure: Author(s). Title. Edition (if not first). Publisher; Year. 5. Kasper DL, Fauci AS, Hauser SL, et al. Harrison’s Principles of Internal Medicine. 21st ed. McGraw-Hill; 2022. // Book title is italicised. Edition abbreviation: “21st ed.” not “21st edition.” Publisher name then semicolon then year. No publisher location required in AMA 11th (removed from earlier editions). No period after the year if a URL follows.

Chapter in an Edited Book // Structure: Chapter Author(s). Chapter title. In: Editor(s), eds. Book Title. Publisher; Year:Pages. 6. Brenner BM, Rector FC. Renal physiology and pathophysiology. In: Jameson JL, Fauci AS, Kasper DL, Loscalzo J, eds. Harrison’s Principles of Internal Medicine. 21st ed. McGraw-Hill; 2022:295-312. // “In:” introduces the book information. Editors listed with initials before last name? No — same format as authors: Last Initials. “eds.” (lowercase, with period) follows the editor list. Book title italicised. Colon then page range at the end.

E-Book 7. Loscalzo J, Fauci A, Kasper D, Hauser S, Longo D, Jameson JL. Harrison’s Principles of Internal Medicine. 21st ed. McGraw-Hill; 2022. Accessed May 10, 2026. https://accessmedicine.mhmedical.com/book.aspx?bookid=3095 // For e-books, add “Accessed [Month Day, Year].” and the URL. Access date is required for online books in AMA because content may be updated or moved.

Edition Information: Only Include It When It Is Not the First Edition

Only include edition information in your reference when citing a second edition or later. First editions do not need “1st ed.” in the reference. For subsequent editions, use the ordinal abbreviation: 2nd ed., 3rd ed., 4th ed., and so on. Place it after the title, before the publisher — not in parentheses.

Citing Websites and Online Sources

Web citations in AMA require more date information than most other styles. AMA wants to know when the page was published, when it was last updated (if that information is available), and when you accessed it. All three can appear in the reference.

Webpage with Author and Full Date Information // Structure: Author(s). Title. Website Name. Published/Updated dates. Accessed date. URL 8. Donahue MP. Heart failure: overview. American Heart Association. Published March 15, 2023. Updated January 10, 2024. Accessed May 16, 2026. https://www.heart.org/en/health-topics/heart-failure/what-is-heart-failure // Include published date and updated date when both are visible. “Published” and “Updated” are written out fully. “Accessed” date is always required for web sources in AMA.

Webpage — Organisation as Author 9. World Health Organization. Depression fact sheet. World Health Organization. Published September 13, 2021. Accessed May 16, 2026. https://www.who.int/news-room/fact-sheets/detail/depression // When the organisation is both author and publisher, you can list it once as the author and omit it as publisher — or include it both places. Either is acceptable in AMA 11th. Consistency within the document matters more than which choice you make.

Webpage — No Author Identified 10. Diabetes overview. National Institute of Diabetes and Digestive and Kidney Diseases. Published December 2016. Accessed May 16, 2026. https://www.niddk.nih.gov/health-information/diabetes/overview // When no individual author is identified, move the page title to the author position. The institutional publisher follows. If no publication date is available, write “Published date unknown” or omit the published line — but always include the accessed date.

The Accessed Date Is Not Optional in AMA

Unlike APA 7th edition (which only requires an access date for content that changes frequently), AMA requires an accessed date for all web-based sources. It goes right before the URL. Format: Accessed Month Day, Year. If you cannot determine when you accessed a source, use today’s date — but make a habit of noting the access date at the time you look the source up, since you will need it for the reference.

Other Common Source Types

Government Report

Author AA, Author BB. Title of Report. Agency Name; Year. URL or doi

Include a report number after the title if one is assigned: Title of Report. Report No. XXXXXX. If published online, add the URL and accessed date.

Thesis or Dissertation

Author AA. Title of Dissertation [dissertation]. University Name; Year. URL

Label in brackets: [dissertation] for a doctoral work, [thesis] for a master’s. Include the awarding institution and year. If accessed through ProQuest or an institutional repository, include the database name and URL.

Conference Presentation or Abstract

Author AA. Title of presentation. Paper presented at: Conference Name; Month Day, Year; Location.

For published conference abstracts in a journal supplement, use the journal article format and note “[abstract]” after the title. Unpublished presentations use the format above.

Package Insert / Drug Label

Drug Name [package insert]. Manufacturer; Year.

Drug package inserts are cited by drug name (which goes in the author position), with “package insert” in brackets after it. This format is specific to medical and pharmacy writing and does not appear in other citation styles.

Clinical Practice Guideline

Organisation Name. Title of Guideline. Publisher; Year. URL

Guidelines from bodies like the ACC, AHA, CDC, or NICE are cited with the organisation as the author. Include the full guideline title in italics, the publisher, year, and URL. If the guideline has a document number or DOI, include it.

Newspaper or Magazine Article

Author AA. Title of article. Publication Name. Month Day, Year:PageNumber.

For online newspaper or magazine articles, substitute the URL for the page number and add an accessed date. Note that newspaper articles are rarely appropriate as primary citations in formal health science writing — use peer-reviewed sources where possible and reserve news sources for context or policy discussion.

Author Name Format

AMA has a specific author format that trips up students coming from other styles. Get this right — it affects every reference in your list.

Situation	AMA Reference List Format	Notes
Single author	`Smith AB.`	Last name, then initials with no periods or spaces between them. Period after the full author entry.
Two authors	`Smith AB, Jones CD.`	Separated by comma and space. No ampersand (&) before the last author — unlike APA.
Three–six authors	`Smith AB, Jones CD, Lee EF, Brown GH.`	List all. Comma between each. Period after the last author’s initials.
Seven or more authors	`Smith AB, Jones CD, Lee EF, et al.`	First three authors, then “et al.” with a period. “et al.” is not italicised in AMA references.
Organisation as author	`World Health Organization.`	Write the full organisation name. No abbreviation in the author position unless the organisation commonly uses one.
No author	Title moves to author position	Start the reference with the title. Do not write “Anonymous” unless the source explicitly credits “Anonymous” as the author.
Editor instead of author	`Smith AB, Jones CD, eds.`	For edited books, follow the editors’ names with “ed.” (one editor) or “eds.” (multiple editors).

No Ampersand Before the Last Author in AMA

APA uses “&” before the last author in a reference: Smith, A. B., & Jones, C. D. AMA does not. In AMA, authors are simply separated by commas throughout: Smith AB, Jones CD. There is no “and” or “&” anywhere in an AMA author list, regardless of how many authors there are. This is a small but consistent difference that citation generators frequently get wrong when switching between styles.

Journal Name Abbreviations

This is the part of AMA citation that takes the most time if you are not familiar with it. Journal names in AMA references are abbreviated — never spelled out in full. The abbreviations are standardised by the National Library of Medicine.

The Rule

Use NLM Abbreviations

Every indexed journal has an official NLM abbreviation. Use it exactly. Do not create your own abbreviation based on guesswork. “Journal of the American Medical Association” → JAMA. “The Lancet” → Lancet. “New England Journal of Medicine” → N Engl J Med.

Where to Find Them

NLM Catalog

Search at ncbi.nlm.nih.gov/nlmcatalog. The journal record shows the NLM abbreviation field. PubMed citations also display abbreviated names — copy from there if you found the article through PubMed.

Formatting

Italicised, No Periods

The abbreviated journal name is italicised in AMA references. There are no periods within the abbreviation — N Engl J Med, not N. Engl. J. Med. A period follows the abbreviated name as sentence punctuation before the year.

One-Word Journals

Not Abbreviated Further

Journals with single-word names — Lancet, JAMA, Nature, Science, Pediatrics — are not abbreviated further. Write the name as it appears. JAMA is already an acronym; do not expand it.

Common Examples

Frequently Cited Journals

N Engl J Med (New England Journal of Medicine) · JAMA · Lancet · BMJ · Ann Intern Med · Circulation · J Clin Oncol · Am J Med · JAMA Intern Med

If Uncertain

Do Not Guess

If you cannot find the official abbreviation for a journal, write out the full name rather than guessing. An unverified abbreviation is worse than no abbreviation. Check PubMed or the NLM catalog before finalising your reference list.

DOIs and URLs in AMA Format

AMA 11th edition handles digital identifiers differently from earlier editions. The rules are cleaner now — and if you are used to older AMA formatting, note what changed.

1DOI Format: doi:10.xxxx — No Space, Lowercase

In AMA 11th, DOIs are formatted as: doi:10.1001/jama.2022.12345. Note: lowercase “doi” with a colon, then the number — no space between the colon and the number, and no “https://doi.org/” prefix. This differs from APA 7th, which uses the full hyperlink format. AMA keeps it shorter: just doi: and the string. Include the DOI at the end of the reference, after the page numbers, followed by a period.

2DOI Takes Priority Over URL

If a journal article has a DOI, use the DOI — do not substitute a database URL. The DOI is more stable and more precise. Database URLs (from PubMed, CINAHL, MEDLINE) change; DOIs do not. If an article has both a DOI and a URL, include only the DOI. If it has no DOI, include the direct URL to the article.

3Accessed Dates for Web Sources Are Mandatory

For any source that is a webpage — not a journal article accessed online, but an actual website — include an accessed date immediately before the URL. Format: Accessed May 16, 2026. This is a hard requirement in AMA, unlike APA where accessed dates are only required for frequently changing content. Journal articles accessed through a database do not need an accessed date; websites do.

4Published and Updated Dates for Websites

For websites, include the published date and the updated/reviewed date if they are both visible on the page. Format: Published January 5, 2022. Updated March 10, 2024. If only one date is visible, include what is available. If no date is visible at all, note “Published date unknown.” — but this should prompt you to consider whether the source is reliable enough to cite.

AMA vs APA vs Vancouver

Three citation styles dominate health science writing. Knowing which is which — and which your programme uses — matters before you write a single reference.

AMA Style

Superscript numbers in the text — no author names or years
Reference list numbered in order of first appearance (citation-sequence)
Journal names abbreviated using NLM abbreviations
Author format: Last Initials (no periods between initials)
6 or fewer authors listed in full; 7+ → first 3 + et al.
DOI format: doi:10.xxxx (lowercase, no URL prefix)
Accessed dates required for all web sources
Standard for JAMA, medical school papers, health sciences

APA Style

Author-date in-text citations: (Author, Year)
Reference list alphabetical by first author’s last name
Journal names spelled out in full, title case
Author format: Last, F. M. (with periods after initials)
3+ authors → Author et al. from first citation
DOI format: https://doi.org/10.xxxx (full hyperlink)
Accessed dates only for frequently changing content
Standard for psychology, education, social sciences

AMA and Vancouver Are Not the Same

Vancouver and AMA both use numbered superscript citations and citation-sequence reference lists — so they look similar at first glance. The differences are in the details: Vancouver uses a slightly different punctuation pattern for journal references, lists up to six authors before et al. (same as AMA), and formats DOIs differently. Vancouver is the style used by most biomedical journals outside the US; AMA is used by American Medical Association publications and many US medical schools. If your programme specifies “Vancouver,” do not use AMA formatting and assume it is close enough. Check your institution’s Vancouver guidance for the exact format required.

Common AMA Errors That Cost Marks

Periods Between Author Initials

Writing “Smith, A.B.” or “Smith A.B.” instead of “Smith AB.” Periods between initials are an APA habit — they do not belong in AMA. No periods between initials, no comma between last name and initials. Just: LastFirst Middle.

LastNameInitials With No Periods

The correct AMA author format is: Smith AB. Two-initial author: Jones CD. Three initials: Lee EFG. No periods within the initials. Period only after the full author entry (or after the last author in a multi-author reference).

Alphabetical Reference List

Sorting the reference list alphabetically by author last name is the APA default. In AMA, references are numbered and listed in the order they first appear in the text. Alphabetising them breaks the link between the superscript numbers in the text and the reference list entries.

Number Entries in Order of First Appearance

Work through your paper from the introduction to the conclusion. The first source cited is reference 1, the second new source is reference 2, and so on. If you add or remove citations during revision, renumber your entire reference list and update every superscript in the text. This is why most writers finalise citations after the text is settled.

Full Journal Names Instead of Abbreviations

Writing “New England Journal of Medicine” instead of “N Engl J Med.” AMA requires NLM abbreviated journal names throughout the reference list. Spelling out full journal names is not an acceptable alternative — it is a formatting error.

Look Up Every Journal Abbreviation

Before submitting, check every journal name in your reference list against the NLM catalog or the PubMed citation for each article. Do not rely on memory or estimation for abbreviations. Journals you know well are just as easy to abbreviate incorrectly as unfamiliar ones.

Wrong DOI Format

Using “https://doi.org/10.xxxx” (the APA format) instead of “doi:10.xxxx” (the AMA format). Or adding a space after the colon: “doi: 10.xxxx.” Both are wrong in AMA. The format is: doi:10.xxxx — lowercase, colon, number, no space.

AMA DOI Format: doi:10.xxxx

Lowercase “doi” then colon then the number string with no space between them. End with a period after the DOI. If you are copying from APA-formatted references, strip out “https://doi.org/” and replace with just “doi:” — that is the only change needed for the DOI element itself.

Missing Accessed Date for Web Sources

Omitting the accessed date for a webpage. Unlike APA, AMA requires an accessed date for all web-based sources. This is a consistent and specific AMA requirement. Missing it is a clear formatting error.

Always Record the Accessed Date for Websites

Build the habit of noting the accessed date when you first look at a web source — not when you write the reference later. The format is: Accessed Month Day, Year. Place it immediately before the URL. For journal articles accessed through a library database, you do not need an accessed date — only for actual webpage sources.

Using the Wrong Punctuation Sequence for Journal References

Adding spaces before the semicolon, putting the issue number outside parentheses, using a hyphen instead of an en dash for page ranges, or placing the DOI before the page numbers. The exact sequence — Year;Volume(Issue):StartPage-EndPage. doi: — must be followed precisely.

Memorise the Journal Reference Sequence

Author(s). Title. Abbrev J. Year;Volume(Issue):Pages. doi:number. Say it, type it, check it against a verified example every time. The semicolon after the year, the colon before pages, the parenthetical issue number — each has a fixed position. One misplaced character is still a formatting error.

Frequently Asked Questions About AMA Citation Format

What is AMA citation format?

AMA is the American Medical Association’s citation system, used in medicine, nursing, public health, dentistry, and allied health fields. It uses superscript Arabic numerals in the text — placed at the point of citation — that correspond to numbered entries in a reference list at the end of the document. References are numbered in the order they first appear, not alphabetically. The current edition is AMA 11th, published in 2020 by Oxford University Press and documented at amamanualofstyle.com. It is the standard style for JAMA and most American Medical Association publications.

How do AMA in-text citations work?

You place a superscript Arabic numeral in the text at the point where you are using the source — after punctuation (commas and periods) but before colons and semicolons. The first source you cite becomes superscript 1, the next new source becomes superscript 2, and so on. If you cite the same source again later in the paper, use the same superscript number it was originally assigned. To cite multiple sources at one point, list the numbers separated by commas or as a range: ^3,5,7 or ^4-6. Author names and publication years never appear in AMA in-text citations.

How do I format a journal article in AMA style?

The AMA journal article format is: Author(s). Article title in sentence case. Abbreviated Journal Name. Year;Volume(Issue):StartPage-EndPage. doi:10.xxxx/xxxx. Key points: author initials have no periods between them; journal names use NLM abbreviations and are italicised; the title is not italicised; year immediately follows the period after the journal name, then a semicolon, then volume, issue in parentheses, colon, page range, period, then the DOI in format doi:10.xxxx. For help with the exact punctuation pattern, see the excerpt examples in the journal articles section of this guide.

How many authors do I list before using et al. in AMA?

If a source has six or fewer authors, list all of them in the reference. If it has seven or more, list only the first three followed by “et al.” — with a period after “al.” This applies to the reference list. In-text citations in AMA never include author names at all, so et al. is not a concern for in-text use. Note: APA uses a different threshold (three or more triggers et al. in-text), so if you work across both styles, be careful not to mix up the rules.

How do I cite a website in AMA format?

The AMA website format is: Author(s) or Organisation. Title of page. Website Name. Published [date if available]. Updated [date if available]. Accessed Month Day, Year. URL. The accessed date is required for all web sources in AMA — unlike APA, where it is only required for frequently changing content. If no author is identifiable, the title moves to the author position. If no publication date is available, write “Published date unknown.” Include the updated date if the page shows one. The URL goes last, with no period after it.

What is the difference between AMA and APA citation?

The core difference is the citation system. AMA uses sequential superscript numbers in the text; APA uses author-date parenthetical citations — (Author, Year). AMA reference lists are ordered by first appearance; APA reference lists are alphabetical. AMA requires abbreviated journal names; APA uses full journal names in title case. Author initials have no periods in AMA; APA uses periods. The DOI format also differs: AMA uses doi:10.xxxx, APA uses https://doi.org/10.xxxx. If your programme is in health sciences, you are almost certainly using AMA. If it is in psychology, education, or social sciences, you are likely using APA. Check your course brief if you are uncertain. For APA guidance, see our APA citation guide.

Do I need to abbreviate journal names in AMA?

Yes. AMA requires NLM (National Library of Medicine) standard abbreviations for all journal names in the reference list. Never spell out a full journal name in an AMA reference. Find the official abbreviation for any indexed journal at the NLM catalog (ncbi.nlm.nih.gov/nlmcatalog) or by looking at the journal’s PubMed record. The abbreviated name is italicised and has no periods within it — just the abbreviated words separated by spaces, followed by a period as the sentence-ending punctuation.

How do I format a DOI in AMA?

AMA 11th edition formats DOIs as: doi:10.xxxx/xxxxx — lowercase “doi,” colon, then the DOI string with no space. This is different from APA, which uses the full hyperlink https://doi.org/10.xxxx. Do not use the APA format in AMA references. Place the DOI at the end of the reference entry, after the page numbers, followed by a period. If you are copying references from a database or citation generator, check whether the DOI has been formatted in APA style and correct it to AMA format before submitting.

Is AMA the same as Vancouver citation style?

Not exactly. Both use numbered in-text superscripts and numbered-by-appearance reference lists, so they look similar. The differences are in the details: punctuation patterns in journal references, publisher location requirements, and some formatting conventions differ between AMA 11th and the Vancouver/ICMJE guidelines. Vancouver is the style used by most international biomedical journals outside the US; AMA is used by American Medical Association publications. If your programme specifies “Vancouver,” request the institution’s specific Vancouver guide — do not substitute AMA and assume they are interchangeable. For full citation guidance across multiple styles, see our citation and referencing support page.

Can I use a citation generator for AMA format?

Citation generators produce a useful first draft, but AMA is one of the styles they handle least reliably. Common generator errors include using APA-format DOIs instead of AMA format, adding periods between author initials, using full journal names instead of NLM abbreviations, and applying the wrong punctuation sequence for journal references. Use a generator to build your starting reference, then check every detail against a verified AMA example or the AMA Manual of Style online. The journal abbreviation in particular almost always needs manual verification. For support with AMA reference lists, see our academic writing services.

AMA References Taking Longer Than Expected?

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What Makes AMA Citations Work — and What Makes Them Fail

The numbered system is actually less work than author-date styles once you understand it. No names in the text. No years to track. Just numbers. The reference list does the heavy lifting.

Where students run into problems is in the reference list details. Author initials without periods. Journal names abbreviated using NLM standards. The exact punctuation sequence for journal articles — year;volume(issue):pages — with no spaces where the style says no spaces. DOIs in AMA format, not APA format. Accessed dates on every web source. These are not arbitrary rules — medical literature depends on precise, reproducible citations so that readers can verify sources quickly.

Three habits make this manageable. First: keep the NLM catalog open while you build your reference list and verify every journal abbreviation as you go. Second: use the exact punctuation template — Author(s). Title. Abbrev J. Year;Volume(Issue):Pages. doi:number — as a literal checklist for each entry. Third: number your references only after the text is finalised. Renumbering mid-draft is time-consuming and introduces errors.

For help with AMA reference lists, citation formatting, and academic writing in health and medical sciences — our citation and referencing support, academic writing services, and proofreading and editing services cover every level of study.

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