Table 2.

Number of original research articles with authors given equal credit categorized by byline position

Byline position of authors receiving equal credit	NEJMa (n=146)	JAMAb (n=69)	Annalsc (n=29)	Lancet (n=132)	BMJd (n=23)	Total1 (n=399)
First two authors	87 (59.6%)	44 (63.8%)	25 (86.2%)	85 (64.4%)	13 (56.5%)	254 (63.7%)
First three or more authors	20 (13.7%)	8 (11.6%)	1 (3.4%)	15 (11.4%)	1 (4.3%)	45 (11.3%)
Last two authors	11 (7.5%)	3 (4.3%)	0	6 (4.5%)	0	20 (5.0%)
First and last author2	2 (1.4%)	5 (7.2%)	0	3 (2.3%)	6 (26.1%)	16 (4.0%)
First two and last two authors	8 (5.5%)	1 (1.4%)	2 (6.9%)	4 (3.0%)	0	15 (3.8%)
Middle authors only	7 (4.8%)	4 (5.8%)	1 (3.4%)	8 (6.1%)	0	20 (5.0%)
First three (or more) authors and last three (or more) authors	3 (2.1%)	1 (1.4%)	0	2 (1.5%)	0	5 (1.3%)
All authors3	0	0	0	7 (5.3%)	2 (8.7%)	9 (2.3%)
Other	8 (5.5%)	3 (4.3%)	0	2 (1.5%)	1 (4.3%)	14 (3.5%)

¹cumulative total across all 5 journals

²including but not limited to articles with only two authors

³excluding articles with only two authors

^aNew England Journal of Medicine

^bJournal of the American Medical Association

^cAnnals of Internal Medicine

^dBritish Medical Journal