Research Guides: Publishing: Authorship

Deciding Who and How Many Authors

Who?

As with most guidelines related to manuscript submission, each journal will have different requirements and expectations for authors. You must check the journal’s website to locate the instructions for authors.

Many journals (including the NEJM, JAMA, and BMJ) use the International Committee of Medical Journal Editors (ICMJE) recommendations.

ICMJE
The ICMJE recommends that authorship be based on the following criteria per their website:

Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data for the work; AND
Drafting the work or reviewing it critically for important intellectual content; AND
Final approval of the version to be published; AND
Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

It is important to note that even those who haven’t met the criteria for authorship should be acknowledged as contributors to your work.

How many?

Generally, most journals are looking for manuscripts written by more than one author but are often not specific regarding the maximum or minimum number of authors. For example:

The NEJM Author Center
“There are no limits as long as each person credited with article authorship meets the criteria for authorship as defined in the International Committee of Medical Journal Editors (ICMJE) recommendations.”
JAMA Instructions for Authors
JAMA cites the ICMJE and adds that “each author should be able to identify which coauthors are responsible for specific other parts of the work and should have confidence in the integrity of the contributions of any coauthors.”
BMJ Authorship
Meanwhile, BMJ, notes "Case reports should have a maximum of four authors," but editors may be willing to make adjustments if you contact them directly.