Reader's guide to critical appraisal of cohort studies: 1. Role and design

At the final page proof stage of this Education and Debate article, some sort of glitch—the cause of which we have yet to fathom—resulted in the first author's name jumping to the end of the authorship line (BMJ 2005;330:895-7, 16 Apr). Paula A Rochon (not Jerry H Gurwitz), therefore, is the first (not the last) author of this paper. This has already been changed on bmj.com.