study, or may be lost-to-follow-up. Since participants in smoking studies are usually reporting outcomes to non-counselors, they may be especially reluctant to reveal suicidal ideation. In addition, most prospective studies did not mention suicide; thus, it is unclear if they did not look for an association of smoking and suicide; they looked but did not find it; they found it but did not report it, or they reported it but it was edited out prior to publication.
