Web-Based Smoking-Cessation Program: Results of a Randomized Trial

Background—Initial trials of web-based smoking-cessation programs have generally been promising. The active components of these programs, however, are not well understood. This study aimed to (1) identify active psychosocial and communication components of a web-based smokingcessation intervention and (2) examine the impact of increasing the tailoring depth on smoking cessation. Design—Randomized fractional factorial design. Setting—Two HMOs: Group Health in Washington State and Henry Ford Health System in Michigan. Participants—1866 smokers. Intervention—A web-based smoking-cessation program plus nicotine patch. Five components of the intervention were randomized using a fractional factorial design: high- versus low-depth tailored success story, outcome expectation, and efficacy expectation messages; high- versus lowpersonalized source; and multiple versus single exposure to the intervention components. Measurements—Primary outcome was 7 day point-prevalence abstinence at the 6-month followup. Findings—Abstinence was most influenced by high-depth tailored success stories and a highpersonalized message source. The cumulative assignment of the three tailoring depth factors also resulted in increasing the rates of 6-month cessation, demonstrating an effect of tailoring depth. Conclusions—The study identified relevant components of smoking-cessation interventions that should be generalizable to other cessation interventions. The study also demonstrated the importance of higher-depth tailoring in smoking-cessation programs. Finally, the use of a novel fractional factorial design allowed efficient examination of the study aims. The rapidly changing interfaces,