New England Journal of Medicine Citation Guide: Step-by-Step Format Tips

Stop struggling with medical citations. Learn to cite accurately every single time!

Citing sources correctly is essential in medical writing, and NEJM uses its own citation style based on the Vancouver system. This guide offers a clear breakdown of how to format citations for the New England Journal of Medicine, one of the most respected journals in the healthcare field.

We’ll cover everything from in-text citation rules, reference list formatting, journal abbreviations, and tools that make the process easier. Whether you're aiming to submit to NEJM or just want to ensure accuracy and professionalism in your work, this guide will keep your citations sharp and compliant.

Overview of NEJM Citation Style

The New England Journal of Medicine (NEJM) follows the Vancouver citation style, as outlined by the International Committee of Medical Journal Editors (ICMJE). This means that all sources are cited using a numbered system, with references appearing in the order they're first mentioned in the text.

Unlike author-date formats, NEJM uses superscript numbers to refer to sources, helping maintain the flow and clarity of dense scientific writing. This system is especially important in medical and clinical research, where accurate referencing supports evidence-based conclusions and maintains academic integrity.

In-Text Citations

NEJM uses a sequential numeric citation format, meaning the first source you cite in your paper is numbered as ¹, and that number follows the same reference throughout.

Superscripts should be placed outside punctuation marks like commas and periods.
When citing multiple sources in one sentence, separate them with commas (e.g., ²,³) or use a hyphen for a range (e.g., ⁴–⁶).
If you cite the same source again, use the same number as its original appearance.

Examples:

Recent studies suggest this may reduce inflammation.¹
Several trials²–⁴ have shown consistent results.
According to Smith et al.,⁵ the findings were conclusive.

Reference List Formatting

The reference list in NEJM style appears at the end of the manuscript and must follow the order of first citation—not alphabetical order.

Each entry should follow these formatting rules:

Authors: Last name followed by initials (no periods). List all authors if there are six or fewer; if more, list the first three followed by “et al.”
Article title: Use sentence case (capitalize only the first word and proper nouns).
Journal title: Use abbreviated journal names (based on Index Medicus).
Publication details: Include year, volume number, and page range.

Example:

Ginsburg GS, Willard HF. Genomic and personalized medicine: foundations and applications. Trans Am Clin Climatol Assoc. 2009;120:43–53.

Abbreviations and Formatting Details

In the NEJM citation style, journal titles must be abbreviated using the official NLM (National Library of Medicine) abbreviations. These can be found through the NLM Catalog and must match exactly, including punctuation.

Journal Articles

Use standard abbreviation for the journal title
Include year, volume number, and full page range
No article title italics or quotation marks
Include DOI if available

Example:

Fauci AS. Emerging and re-emerging infectious diseases: the perpetual challenge. Acad Med. 2005;80(12):1079–1085. doi:10.1097/00001888-200512000-00002

Books

List author(s), book title in sentence case, edition (if not the first), place of publication, publisher, and year

Example:
2. Murray PR, Rosenthal KS. Medical Microbiology. 8th ed. Philadelphia: Elsevier; 2016.

Book Chapters

Include chapter author, chapter title, editors, book title, edition, publication location, publisher, year, and page range

Example:
3. Katzung BG. Introduction to pharmacology. In: Katzung BG, ed. Basic and Clinical Pharmacology. 14th ed. New York: McGraw-Hill Education; 2018:1–12.

Online Sources

Include author (if available), title, website name, publication or update date, and URL with access date

Example:

4. World Health Organization. COVID-19 dashboard. WHO. Published 2023. Accessed August 15, 2023. https://covid19.who.int/

Additional Resources

For researchers submitting to NEJM or working in the medical field, these resources can ensure your citations meet professional standards and save you time during the writing process.

ICMJE Recommendations

The International Committee of Medical Journal Editors (ICMJE) sets the standard for NEJM’s citation style. Their guidelines are the backbone of many medical and health science journals.

You’ll find specific instructions on:

Author formatting
Reference order and structure
Abbreviations and publication details

You can view the full citation guidelines at the ICMJE official site.

NEJM Author Center

The NEJM Author Center provides submission-specific formatting instructions. It includes:

Preferred citation style
Referencing of preprints and datasets
Guidelines for in-text citation and reference lists

Writers preparing manuscripts for NEJM should always cross-check their formatting with this official source.

Citation Management Tools

Tools like EndNote, Zotero, and Mendeley make it easier to:

Import references from databases
Automatically format citations in NEJM style
Keep references organized across multiple projects

These tools can save hours of manual formatting and help avoid citation errors—especially when juggling dozens of references.

Make Citation Effortless with the Right Tools

Following the NEJM citation style is key to maintaining clarity and credibility in medical writing. From properly placing superscript numbers to formatting a consistent reference list, every detail counts.

For a smoother writing experience, try Jenni AI. It can help you stay organized, save time, and keep your citations clean and compliant!