Use the author’s surname followed by initials without periods. In listed references, the names of all authors should be given unless there are more than 6, in which case the names of the first 3 authors are used, followed by “et al.” Note: The NLM guidelines do not limit the number of authors listed but, for space considerations, we have elected to depart from the NLM guidelines on this point.
Note spacing and punctuation. Do not use and between names. Roman numerals and abbreviations for Junior (Jr) and Senior (Sr) follow author’s initials. Note: Although NLM uses “2nd,” “3rd,” and “4th,” JAMA and the Archives Journals prefer II, III, and IV, unless the author prefers arabic numerals.
Also, although JAMA and the Archives Journals, in bylines, make a distinction between a group of individuals writing for a group and a group of individuals writing as a group or in addition to (ie, and) a group (see 5.1.7, Legal and Ethical Considerations, Authorship Responsibility, Group and Collaborative Authorship), this distinction is not retained in the NLM database and hence in MEDLINE. If authors, in their reference lists, provide this information, the for or and will be retained, but if this information is not provided, the reference will use the individuals named and the group name, without for or and. Both styles are illustrated in the examples below. Note that the group name is preceded by a semicolon rather than a comma (to show, as noted in 3.1, Reference Style and the Uniform Requirements, that the information that follows is related to what precedes it but somehow distinct) and that articles (eg, the) in the group name are removed.
Doe JF, Roe JP III.
Doe JF, Roe JP III, Coe RT Jr, Loe JT Sr, Poe EA, van Voe AE.
Doe JF, Roe JP III, Coe RT Jr, et al.
1 author for or and a group:
Doe JF; Laser ROP Study Group.
Doe JF; for Laser ROP Study Group.
Doe JF; and Laser ROP Study Group.
>6 authors for or and a group
Doe JF, Roe JP III, Coe RT Jr, et al; Laser ROP Study Group.
Doe JF, Roe JP III, Coe RT Jr, et al; for Laser ROP Study Group.
Doe JF, Roe JP III, Coe RT Jr, et al; and Laser ROP Study Group.
When mentioned in the text, only surnames of authors are used. For a 2-author reference, list both surnames; for references with more than 2 authors or authors and a group, include the first author’s surname followed by “et al,” “and associates,” or “and colleagues.”
Doe7 reported on the survey.
Doe and Roe8 reported on the survey.
Doe et al9 reported on the survey.
Note: Do not use the possessive form et al's; rephrase the sentence.
The data of Doe et al9 support our findings.
In material that is less clinical (eg, book reviews, historical features, letters to the editor), the author’s first name or honorific may be used at first mention:
We agree with Dr Tayeb that the prevalence of domestic violence is difficult to determine.
In Growing Up Fast, Joanna Lipper profiles 6 teenaged mothers living in Pittsfield, Massachusetts, at the turn of the 21st century.