Participant- and study-related characteristics predicting treatment completion and study retention in an adolescent smoking cessation trial.

PURPOSE: To determine which factors predict smoking cessation treatment completion and retention among adolescents. METHODS: In a multisite, randomized, controlled trial, the efficacy of motivational interviewing was compared with structured brief advice for smoking cessation and reduction in adolescents (n = 355) aged 14-18 years (55% female, 45% black, 12% Hispanic). Treatment spanned 12 weeks, with follow-up assessments at 24 weeks. Treatment completion was defined as completion of all five counseling sessions. Study retention was defined as completing the 24-week assessment. Participant and study variables served as predictors of treatment completion and retention. RESULTS: In all, 79% of participants completed all five counseling sessions and the same percent completed the 24-week assessment. Black race, precontemplation stage to cut back, and shorter length of time between the baseline assessment and the first counseling session were significantly associated with treatment completion. For every 7.5-day delay in starting treatment after the baseline visit, there was a 50% decrease in the odds of completing all five treatment sessions. Retention at 24 weeks was predicted by black race, younger age, greater maternal education, expectations of graduating college, and structured brief advice intervention. CONCLUSIONS: High rates of treatment completion and study retention can be achieved in a multisession, behavioral intervention for adolescent smoking cessation. Findings suggest that treatment should begin soon after the intake session to maximize treatment completion. Enhanced efforts to retain older adolescents and youth with lower academic goals and lower family income will be important in future studies.

The efficacy of motivational interviewing versus brief advice for adolescent smoking behavior change.

OBJECTIVE: In this study we sought to evaluate the efficacy of motivational interviewing (MI) compared with structured brief advice (SBA) for adolescent smoking behavior change. METHODS: Participants (N=355) were randomly assigned to 5 sessions of either MI or SBA. The primary outcomes were attempts to reduce and to quit smoking, smoking reduction, and cotinine-validated 7-day point-prevalence smoking abstinence at the end of treatment (week 12) and the 24-week follow-up. RESULTS: White adolescents were ∼80% less likely to attempt to cut back (odds ratio [OR]: 0.21; confidence interval [CI]: 0.08-0.53) and >80% less likely to attempt to quit smoking compared with black adolescents (OR: 0.17 [CI: 0.06-0.46]). Adolescents who were at least planning to cut back or quit smoking at baseline were almost 3 times more likely to attempt to cut back (OR: 2.87 [CI: 1.26-6.52]) and to attempt to quit smoking (OR: 3.13 [CI: 1.19-8.26]). Adolescents who received MI were ∼60% less likely than adolescents who received SBA to try to quit smoking (OR: 0.41 [CI: 0.17-0.97]). However, adolescents who received MI showed a greater reduction in cigarettes smoked per day than adolescents who received SBA (5.3 vs 3.3 fewer cigarettes per day). There were no statistically significant differences between MI and SBA in smoking abstinence (5.7% vs 5.6%, respectively). CONCLUSIONS: The effects of MI on adolescent smoking behavior change are modest, and MI may best fit within a multicomponent smoking cessation treatment approach in which behavior change skills can support and promote smoking behavior change decisions.