Predictors and Consequences of Combustible Cigarette Smokers' Switch to Standardized Research E-Cigarettes

The investigators will enroll 120 conventional cigarette smokers who report smoking at least 3 cigarettes/day. Following completion of baseline questionnaires and a week of ecological momentary assessments (EMA) tracking participants usual smoking behavior, participants will be stratified (by sex) and randomly assigned with a 1:1 allocation ratio to one of two conditions: 1) to receive SREC pods in their usual flavor (N = 60); and 2) to receive SREC pods in their choice of flavor (N = 60). The SREC pods used in this study come in tobacco, menthol, blueberry, and watermelon flavors. No other flavors will be available to use with the SREC. Counseling at Week 2. Participants in both conditions will receive brief behavioral counseling on reducing their combustible cigarette use by substitution with SREC. Staff will work with participants to set individual goals for reduction during this first week, with the goal of achieving at least 75% reduction in the number of combustible cigarettes smoked by the end of the week, and all are encouraged to reduce further. Participants will also be told not to use any other combustible tobacco products. During the week, participants will complete a daily text or web report on number of cigarettes smoked and SREC pods used. Week 3 Visit. Participants will bring back all used and unused pods for adherence counts, complete a brief questionnaire about subjective reactions and potential adverse effects, and provide breath CO. Participants will meet with study staff to review their progress with switching to SREC and receive continued behavioral counseling to substitute SREC for cigarettes. Participants will receive SREC refill pods and will start a second 7-day EMA protocol. Week 4 Visit. EMA debriefing to check for compliance and any problem reports; return of used and unused pods, complete assessments; review of progress with switching to SREC. Participants will receive a 2 week supply of SREC pods. Weeks 5-13. Participants return to the study office every 2 weeks to return pods, receive a new supply, and provide breath CO. During the week, participants will continue daily use reports via web/text. Week 14 (End-of-Treatment). Participants return to the study office to complete a full assessment battery. They will be encouraged to continue to stay off/reduce all combustible cigarettes, but will not receive additional SREC refills from the study. Week 18 (One Month Follow-up). Participants complete a final survey.