References in American Medical Association (AMA) are quite similar to those in APA in terms of their structure. This style mainly differs from other common styles, such as APA or MLA, through its in-text citations, which use superscripts, and the order in which references are organized.
In-text citations
References are cited in numerical order through superscript Arabic numerals (“7” instead of “VII”)
Superscripts are placed outside periods and commas
Ex: “Although exposure to instrumental music yielded far more consistent results in terms of recovery time,7 exposure to music with upbeat lyrics did demonstrate the fastest recovery time overall.”
Place superscripts inside colons and semicolons
Ex: “The study yielded the following result7: instrumental music more consistently affected recovery times.”
For using multiple sources in a single in-text citation:
References in sequence can be joined by a hyphen
Ex: for 2,3,4,5,6 (2-6)
References out of sequence should be separated by a comma
Ex: for 3,5,6,7,8,12 (3, 5-8, 12)
Avoid using a superscript after a number or abbreviated unit of measurement
Ex:
Avoid: This study included an experimental cohort of 5712 patients.
Instead: This study included an experimental cohort12 of 57 patients.
Avoid: The optimal exposure time for lyrical music was 30 min9.
Instead: The optimal exposure time for lyrical music9 was 120 min.
When enough superscripts are used to create a gap in the text (typically 20 characters or more, including spaces and punctuation) then use an asterisk and list the reference numbers in a footnote
Ex: The results revealed that specialist administered music therapy could reduce length of stays in recovery wards by up to 2 weeks*
In the footnote: *References 1, 3, 4, 7-9, 12, 14, 15, 20, 24, 30, 35
If this needs to be done more than once, use an asterisk (*) for the first set of references, a dagger (†) for the second, and double dagger (††) for the third instance
References
Note: Unlike other common citation styles that alphabetize their reference lists, like APA or MLA, AMA organizes references numerically in the order they appeared in the paper.
Books
Author(s). Book Title. Edition number (if it is the second edition or above). Publisher’s name; copyright year.
E-books (books accessed online)
Author(s). Book Title. Edition number (if it is the second edition or above). Publisher’s name; copyright year. Accessed [date]. URL. (verify that the link still works as close as possible to publication)
Author(s) [or the name of the organization responsible for the information]. Title. Name of the website. Accessed [date]. URL. (verify that the link still works as close as possible to publication)
Author formatting
Write authors’ surnames followed by their initials without periods. All authors’ names should be listed, unless there are more than six. If this is the case, only include the first three authors, followed by “et al.”
For one author: Smith JA.
For two authors: Smith JA, Doe LM.
For three to six authors: Smith JA, Doe LF, Jones ME.
For seven or more authors: Smith JA, Doe LF, Jones ME, et al.