Figure 2.

Study timeline. Target days of visits (relative to the day 0, the target quit day), are shown at bottom on the timeline. Intervals between visits varied slightly across subjects. Screening visits included a group orientation and an individual visit including a physical exam. Electronic Diary (ED) training was conducted at the next visit and the 2-day ED training period (noted as T) followed. The ED assessment period was parsed into a 1-week pre-treatment baseline period, a 1-week treatment run-up period, and a 4-week post-quit mediator assessment period, as shown in the lowest level of the figure. Counseling sessions began 1-week pre-treatment and were offered at this and the following 7 visits. Medication treatment began 1-week pre-quit (at 150 mg) per day, increased to 300 mg per day on day −4, and continued until day 56. The abstinence outcome used in analyses (noted as 7-day Abst in the figure) was intent-to-treat complete abstinence (not even a puff) in the week preceding the final visit confirmed by CO (collected at all visits) and not disconfirmed by serum cotinine testing.