[3.6] Use a superscript number1 in-text to cite sources of information. Superscript numbers are in order of citation (the first citation is 1, the next is 2, and so on). If you use the same source again, you keep the original number (i.e. the source you used for the first citation is always 1, even if you use it again at 6).
A reference may be cited in the text, and additionally can be added to a figure, table or box in your work. It is acceptable for the reference to be cited only for a table, figure, box and not in the text, but it must be in numerical sequence with the references cited in the text.
For more information, see the section on paraphrasing, summarising, and quoting in the Successful Academic Writing guide.
Superscript numbers: The numbers in text are in superscript and occur at the end of the clause in which you used the information.1 They occur outside “quotation marks,”2 commas,3 (parentheses)4 and full stops.5 However, they occur inside semicolons6; and colons7:
Important notes:
As reported previously,1,3–8,19
The derived data were as follows3,4:
Re-use numbers for the same source: Citations should be numbered sequentially, that is, the first source you cite is 1, the second source is 2, and so on. However, once you have given a source a number, it will keep that number throughout your paper. So, if you use your first source again, no matter how often you use it, it is still 1.
Relationship between in-text citations and the reference list: Your reference list follows the order of the numbers used in the text. The first source you cite in the text is 1 and the reader will look for number 1 in the reference list to find the full citation; the fifth source you use is 5 and the full citation is listed at number 5 in the reference list (and so on).
Schroder JN, Patel CB, DeVore AD, et al. Transplantation Outcomes with Donor Hearts after Circulatory Death. N Engl J Med. 2023;388(23):2121-2131. doi:10.1056/NEJMoa2212438
In-text
These side effects can have implications for the patient's mental health, as numerous studies have shown.1,3,6-9
The 2 largest studies to date included 26 patients2 and 18 patients.3
Westman5(pp3,5),9 reported 8 cases in which vomiting occurred.
Epstein LH, Wilfley DE, Kilanowski C, et al. Family-Based Behavioral Treatment for Childhood Obesity Implemented in Pediatric Primary Care: A Randomized Clinical Trial. JAMA. 2023;329(22):1947-1956. doi:10.1001/jama.2023.8061
In the medical sciences, you should only use a direct quote if the exact wording is important. You should be paraphrasing the information as much as possible. With paraphrasing it is not standard practice to use page numbers. However they can be used if you feel it is necessary for clarification.
Should you need to refer to the exact wording used by the authors, you must put the quote in double quotation marks and use a page number next to the in-text citation. Put the page number in brackets directly after the reference number, with no space. This should all be in superscript.
Example
In-text
Rey's support of the Mad Dog theory is equivocal, and he states "I’m not defending Mad-doggery because I believe it."3(p125)
[3.7]
If including author names in the text of a sentence, use surnames and add the citation number after the author’s surname.
When you are using information that was originally published in a source you have not read (e.g. quotes, statistics or data), but was cited in a source you have read, this is called secondary citations or secondary referencing. Generally speaking, you should cite the work you have in front of you. Secondary citations should be used sparingly, if at all. The only reason to use a secondary citation is if you cannot get access to the original. Ideally, you should consider using another source for your information. If the work you have read is synthesising information from various sources, for example, a systematic review, and you are paraphrasing their work, then you only need to cite the work you have read.
If it is unavoidable, give the full citation details for both sources, using "Cited by:" (for information/data) or "Quoted by:" (for quotes) to join them.
Scenario & example
You have been reading a journal article by Winchester, which gives a quote by Smith and Wesson, and you want to use that quote. In your reference list, cite: Smith and Wesson (complete reference). Quoted by: Winchester (complete reference).
In-text
Smith and Wesson1(p6) noted the "complete irrelevance of this kind of data" in advanced discussions of this nature.
Reference list
There are several medical journals that follow the AMA referencing style. You can refer to them to observe the formatting of in-text references and reference lists. Here are some examples: