Measured domains available from both studies included (a) descriptive and diagnostic measures, (b) level of nicotine dependence, and (c) smoking outcomes. Participants provided background information including age, gender, years of education, marital status, number of years of regular smoking, and average number of cigarettes per day. Current and past Axis I diagnoses were determined with the Structured Clinical Interview for DSM-IV Non-patient Edition (39). Severity of nicotine dependence was assessed using the Fagerström Test of Nicotine Dependence (FTND) (40), a six-item measure with total scores ranging from 0 to 10, with higher scores indicating higher levels of nicotine dependence. In an effort to characterize two key clinical milestones, the focus of the present investigation is on two separate phenotypes during the period of treatment. The primary outcome of interest was time to first lapse defined as the first time smoking a single puff or more of a cigarette since the quit day. We then examined point-prevalence abstinence at end of treatment (EOT). In an effort to reduce multiple comparisons, we did not evaluate follow-up post EOT in the present investigation,
