A Guide to AMA Style (American Medical Association)

You’re writing a nursing case study or medical research paper, and the citation style is unlike any other. Instead of (Author, Date), you see superscript numbers like this.¹

Welcome to AMA style. The American Medical Association (AMA) style is the standard for medical and health science writing. It is a numbered citation system designed for clarity and precision in scientific communication.

This guide is your foundational resource for AMA 11th edition. We will cover the “macro” context (how the numbered system works) and the “micro” skills (how to format your citations and reference list).

What is AMA Style?

AMA Style is the citation and formatting guide of the American Medical Association, as detailed in the *AMA Manual of Style* (11th edition). It is the standard for journals like *JAMA* and many medical professions.

AMA vs. APA (Numbered vs. Author-Date)

Do not confuse AMA with APA. They are used in similar fields but are formatted differently.

AMA style is similar to IEEE style, but with different punctuation and formatting rules.

General Paper Formatting (AMA 11th Ed.)

As this guide from Tulane University summarizes, AMA formatting is straightforward.

• Margins: 1-inch margins on all sides.
• Font: A standard, readable font (e.g., Times New Roman 12pt or Calibri 11pt).
• Spacing: Double-space the entire paper, including the title page, abstract, text, and references.
• Title Page: Create a separate title page that includes:
  • Paper Title (centered)
  • Author Name(s) and Affiliation(s)
  • Course Information (for student papers)
  • Word Count
  • Corresponding Author contact info (for professional papers)
• Abstract: Often required. A structured (with headings like Objective, Methods) or unstructured (single paragraph) summary.

AMA In-Text Citations: Superscript Numbers

AMA in-text citations are superscript numbers. They are simple and clean.

The Basic Rule: ¹

The citation is a superscript number placed in the text. It should be placed *after* punctuation (like periods or commas).

• Correct: The study confirmed these results.¹
• Incorrect: The study confirmed these results¹ .

Numbering: In Order of Appearance

The first source you cite is ¹. The second source you cite is ². The third is ³. This continues for the whole paper. The list is not alphabetical.

Citing the Same Source Multiple Times

If you cite the first source again later, you re-use the same number ¹.

• Example: The initial theory was proposed by Smith.¹ Later, this theory was expanded.² We based our method on the original work.¹

Citing Multiple Sources at Once

If one sentence is supported by several sources, group the numbers, separated by commas. Use a hyphen (-) for a range.

• Example (multiple): …as shown in previous studies.²˒³˒⁵
• Example (range): …as shown in previous studies.²⁻⁵

Note on Page Numbers: To cite a specific page, you must add it in parentheses after the superscript, e.g., …as Smith¹(p45) argued. This is common for direct quotes.

How to Format the “References” List

The “References” list is the numbered list at the end of your paper. It provides the full citation for each in-text number.

Core Formatting Rules

1. New Page: Start the “References” section on a new page.
2. Title: Use the heading “References.” It can be centered or flush-left, depending on your instructor’s preference (flush-left is common).
3. Numerical Order: The list is not alphabetical. It is a numbered list that follows the order of appearance in your paper (1, 2, 3…).
4. No Indent: Entries are *not* indented. They are formatted as a simple numbered list, flush-left.
5. Author Format: Use author last names and first/middle initials (e.g., Smith JK). Do not use commas between names or periods after initials.
6. Title Format:
   • Article/Chapter Titles: Use Sentence case.
   • Journal/Book Titles: Use *Italics* and Title Case.

Common AMA Reference Examples (11th Ed.)

AMA style is very compact. Note the specific punctuation (or lack thereof).

Journal Article (with DOI)

Book

Chapter in an Edited Book

Website