IEEE citation uses bracketed numbers in the text that point to a numbered reference list, and is standard across engineering and computer science. AMA citation, used widely in medicine, uses superscript numbers instead. Both are numeric systems, but they differ in formatting, ordering and discipline.
This guide explains how each style handles in-text markers and reference entries, with worked examples and a side-by-side table.
IEEE: numbers in square brackets
In IEEE style, each source is assigned a number the first time it is cited, in square brackets, and that number is reused for every later citation of the same source. References are listed in the order they first appear — not alphabetically.
- In-text: Recent work on neural search has improved recall [1], and later studies confirmed it [2], [3].
- Reused number: The original architecture [1] remains the baseline.
- As a noun: As shown in [4], latency dropped sharply.
A reference-list entry abbreviates author first initials and places the number in brackets:
[1] J. Smith and A. Jones, “A scalable indexing method,” IEEE Trans. Knowl. Data Eng., vol. 33, no. 4, pp. 110–128, 2021.
AMA: superscript numbers
AMA style places superscript numerals after the relevant text, again numbered in order of first appearance. The reference list follows the same numeric order. AMA dominates clinical and biomedical journals.
- In-text: Adherence improved across the cohort.1
- Multiple sources: Several trials reported the same effect.2,3
- Range: The pattern held across studies.4-6
A reference entry uses journal abbreviations and a specific punctuation pattern:
1. Smith J, Jones A. Outcomes in the treatment cohort. J Clin Res. 2021;12(3):110-128.
IEEE versus AMA at a glance
| Feature | IEEE | AMA |
|---|---|---|
| Discipline | Engineering, computer science | Medicine, biomedicine |
| In-text marker | Square brackets [1] | Superscript 1 |
| List order | Order of appearance | Order of appearance |
| Author names | Initials before surname: J. Smith | Surname then initials: Smith J |
| Title style | Article title in quotes | Article title, no quotes |
| Journal name | Abbreviated, italic | Abbreviated, italic |
Why discipline drives style choice
Numeric styles keep the running text uncluttered, which suits dense technical and clinical writing where a single sentence may lean on several sources. IEEE’s bracketed numbers double as compact cross-references to equations, figures and prior work; AMA’s superscripts keep medical prose readable at speed. Compare this with author-date approaches in our guide to Harvard referencing, where the author’s name carries into the sentence.
For a wider map of the field, see citation styles compared, and for general technique, our practitioner guide to citing sources.
Common pitfalls
The most frequent IEEE error is alphabetising the reference list — it must follow first-appearance order. The most frequent AMA error is mixing in author-date phrasing (“Smith showed¹”) inconsistently; keep the superscript doing the work. In both styles, every number in the list must be cited at least once in the text, and vice versa. Our for authors guidance covers reference hygiene before submission.
How citation style fits research outputs metadata
Citation style governs the visible reference; controlled vocabulary in our dictionary and contributor attribution through CRediT govern the structured metadata around it. Together they make a paper’s outputs machine-readable. Explore more in research outputs.
Frequently asked questions
Are IEEE and Vancouver the same?
They are close cousins — both numeric, both ordered by appearance — but differ in formatting detail, and Vancouver is associated with biomedicine while IEEE is associated with engineering. AMA is itself a Vancouver-derived medical style.
Do IEEE numbers go inside or outside punctuation?
IEEE brackets typically sit before the full stop, treated as part of the sentence: “…confirmed the result [2].”
Can I cite the same AMA source twice?
Yes — reuse its original number every time it appears, just as in IEEE.
Which style should a computer science thesis use?
IEEE is the conventional default for computer science and electrical engineering, but always follow your department’s or publisher’s stated requirement.
