Pitkin 2000.

Methods	Before and after study; date, volume and page numbers of articles were masked and were numbered accoridng to a computer‐ generated set of random numbers
Data	100 articles; first 50 original contributions in JAMA 1998;278 and last 50 original contributions in JAMA 1998;280
Comparisons	Quality improvement initiative in JAMA;
Outcomes	Overall deficiencies in abstracts; non‐trivial deficiencies; data inconsistent between abstract and text; both above 2 deficiencies; unjustified conclusions
Notes	k = 0.89 for agreement between the 2 evaluators