AMA Style Guide
The American Medical Association (AMA) documentation style is widely used for writing in the biomedical sciences.
The current 11th edition of the AMA Manual of Style is available:
AMA Style uses superscripts in the text, which correspond to an entry in a “References” section at the end of the paper. Number your references at the end of your document in the order they first appear in the text; do not alphabetize.
Use the author’s last name followed by initials and without periods in reference lists. List all authors if six or less; for more than six authors list the first three followed by “et al.”
Journal titles are abbreviated as shown in the National Library of Medicine Catalog.
In Text Citations
Cite each reference in text, figures, tables, or boxes with a superscript number, in the order first cited. Place superscript numbers after a comma or period, but before a semicolon or colon. Use the same superscript number each time you refer to that same source.
Example: The two largest studies to date included 26 patients2 and 18 patients.3
Using Author Names in a Sentence
Use only the author’s surname when referring to them in your text. When there are two authors, list them both. For references with more than two authors or authors and a group, include the first author’s surname followed by “et al,” “and coauthors,” or “and colleagues.”
Doe7 reported on the survey.
Doe and Roe8 reported on the survey.
Doe et al9 reported on the survey.
For a direct quote, include the page number after the citation superscript number.
Example: Smith claims that “without knowledge of AMA style, most medical scholars will find it difficult to publish.”2(p21)
Online Journal Article with DOI
Lohela TJ, Lilius TO, Nedergaard M. The glymphatic system: implications for drugs for central nervous system diseases. Nat Rev Drug Discov. 2022;21(10):763-779. doi: 0.1038/s41573-022-00500-9
Note: Use a DOI instead of a URL whenever one is provided. No accessed date is required when using a DOI.
Online Journal Article without DOI
Shukla H, Meldrum A, Boyd D. Dental and oro-facial features of Foetal Anticonvulsant Syndrome. New Zealand Medical Journal. 2023;136(1579):24-35. Accessed August 2, 2023. https://journal.nzma.org.nz/journal-articles/dental-and-oro-facial-features-of-foetal-anticonvulsant-syndrome
Print Journal Article
Rainier S, Thomas D, Tokarz D, et al. Myofibrillogenesis regulator 1 gene mutations cause paroxysmal dystonic choreoathetosis. Arch Neurol. 2004;61(7):1025-1029.
Perez-Pena R. Children in shelters hit hard by asthma. New York Times. March 2, 2004. http://www.nytimes.com/2004/03/02/nyregion/02asthma.html. Accessed December 2, 2022.
Note: Use section and/or pages in place of URL for citing a print newspaper.
Etzel RA, Balk SJ, eds. Pediatric Environmental Health. American Academy of Pediatrics; 2011.
Adkinson NF Jr, Bochner BS, Burks W, et al, eds. Middleton’s Allergy: Principles and Practice. 8th ed. Saunders; 2014.
Prince M, Glozier N, Sousa R, Dewey M. Measuring disability across physical, mental, and cognitive disorders. In: Regier DA, Narrow WE, Kuhl EA, Kupfer DJ, eds. The Conceptual Evolution of DSM-5. American Psychiatric Publishing Inc; 2011:189-227.
Government Report or Corporate Author
World Health Organization. Equitable access to essential medicines: a framework for collective action. http://whqlibdoc.who.int/hq/2004/WHO_EDM_2004.4.pdf. Published March 2004. Accessed December 16, 2022.
Kasper DL, Fauci AS, Longo DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison’s Principles of Internal Medicine. 19th ed. McGraw-Hill; 2015:chap 32. Accessed February 10, 2023. http://www.harrisonsim.com/index.php
Chapter in an edited eBook
Sudarsky L. Gait and balance disorders. In: Kasper DL, Fauci AS, Longo DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison’s Principles of Internal Medicine. 19th ed. McGraw-Hill; 2015:chap 32. Accessed September 21, 2023. http://www.harrisonsim.com/index.php
Personal communications should not be included in the list of references but can be cited in the text if used judiciously. Documentation should be provided to support personal communication; oral communication should be supported in writing.
According to a letter from H. E. Marman, MD, in August 2022 …
Similar findings have been noted by Roberts6 and by H. E. Marman, MD (email, August 15, 2022).
According to the manufacturer (H. R. Smith, PhD, Pharma International, written communication, May 1, 2022), the drug became available in Japan in January 2014.
Smith R. Evidence-Based Medicine: An Oral History. The JAMA Network and the BMJ. 2014. Accessed October 14, 2022. https://ebm.jamanetwork.com/
Moyers B. On Our Own Terms: Moyers on Dying. DVD. Thirteen/WNET; 2000. https://billmoyers.com/series/on-our-own-terms-moyers-on-dying/
Figures & Images
Häggström M. Liver (transparent). Wikimedia Commons. https://commons.wikimedia.org/wiki/File:Liver_(transparent).png. Published October 2, 2010. Accessed August 3, 2023.
International Society for Infectious Diseases. ProMED-mail. Accessed February 10, 2016. http://www.promedmail.org
Charlton G. Internal linking for SEO: examples and best practices. SearchEngineWatch. Accessed February 10, 2023. https://searchenginewatch.com/sew/how-to/2428041/internal-linking-for-seo-examples-and-best-practices
Recommendations for primary care practice. US Preventive Services Task Force. Accessed March 9, 2023. https://www.uspreventiveservicestaskforce.org/Page/Name/recommendations
- For U.S. Legal References, see AMA Manual of Style section 3.16.
Because legal citations are complex, the AMA refers writers to the latest edition of The Bluebook: A Uniform System of Citation.
Questions & Help
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