Participants from both the sites received identical assessments and treatments. At an initial visit to the smoking clinic, participants provided a 40 mL blood sample and completed a set of standardized self-report questionnaires. Baseline nicotine dependence was assessed via the FTND (64). All participants received 10 weeks of either placebo or bupropion. Bupropion treatment was delivered according to the standard therapeutic dose (150 mg/day for the first 3 days, followed by 300 mg/day). All participants also received seven sessions of standardized behavioral group counseling, focusing on self-monitoring and behavioral modification approaches. All participants were instructed to quit smoking on a TQD 2 weeks after initiating medication and counseling. Smoking status was assessed by telephone interview at the EOT (8 weeks post-TQD) and at 6 months after the TQD using a validated timeline followback method (65). Interviewers were blind to study group assignment. Participants who reported complete abstinence (not even a puff of a cigarette) for at least the 7 days prior to the assessment were asked to complete an in-person visit for biochemical verification of abstinence. Saliva cotinine testing was
