Randomized Controlled Trial of a Smartphone Application as an Adjunct to Acceptance and Commitment Therapy for Smoking Cessation

There is a major public health need for innovative and efficacious behavioral and cognitive interventions for smoking cessation. This randomized controlled trial evaluated the efficacy of an acceptance and commitment therapy (ACT) smartphone application in augmenting ACT group treatment for smoking cessation. One hundred fifty adults smoking 10 or more cigarettes per day were randomly assigned to 6 weekly group sessions of behavioral support, ACT, or ACT combined with the smartphone application. Access to the app was provided from the start of the inperson treatment until the 6-month follow-up assessment. Participants were encouraged to make their quit attempts after the third session, and the posttreatment assessment occurred 3 weeks later. Measures of smoking status and ACT processes were obtained at baseline, posttreatment, and 6-month follow-up. Biochemically verified quit rates in the combined, ACT, and behavioral support groups were 36% (p = .079 relative to ACT; p = .193 relative to behavioral support), 20% (p = .630 relative to behavioral support) and 24% at posttreatment, as compared with 24% (p = .630 relative to behavioral support), 24% (p = .630 relative to behavioral support) and 20% at follow-up. There was no significant difference (p = >.999) in the primary outcome of biochemically verified 7-day point-prevalence abstinence at 6-month follow-up between the combined and ACT groups. The combined group reported significantly greater smoking reduction, acceptance and present-moment awareness than the behavioral support group at posttreatment, but not at follow-up. There were no significant differences between the groups in positive mental health. Contrary to hypotheses, the ACT group did not display significant improvements in positive mental health or ACT processes relative to the behavioral support group at posttreatment or follow-up. Implications and directions for future research are discussed.