摘要：Background Tobacco smoking remains the leading cause of preventable death and disease worldwide.Digital interventions delivered through smartphones offer a promising alternative to traditional methods, but little is known about their effectiveness.Objective Our objective was to test the preliminary effectiveness of Quit Genius, a novel digital therapeutic intervention for smoking cessation.Methods A 2-arm, single-blinded, parallel-group randomized controlled trial design was used.Participants were recruited via referrals from primary care practices and social media advertisements in the United Kingdom.A total of 556 adult smokers (aged 18 years or older) smoking at least 5 cigarettes a day for the past year were recruited.Of these, 530 were included for the final analysis.Participants were randomized to one of 2 interventions.Treatment consisted of a digital therapeutic intervention for smoking cessation consisting of a smartphone app delivering cognitive behavioral therapy content, one-to-one coaching, craving tools, and tracking capabilities.The control intervention was very brief advice along the Ask, Advise, Act model.All participants were offered nicotine replacement therapy for 3 months.Participants in a random half of each arm were pseudorandomly assigned a carbon monoxide device for biochemical verification.Outcomes were self-reported via phone or online.The primary outcome was self-reported 7-day point prevalence abstinence at 4 weeks post quit date.Results A total of 556 participants were randomized (treatment: n=277; control: n=279).The intention-to-treat analysis included 530 participants (n=265 in each arm; 11 excluded for randomization before trial registration and 15 for protocol violations at baseline visit).By the quit date (an average of 16 days after randomization), 89.1% (236/265) of those in the treatment arm were still actively engaged.At the time of the primary outcome, 74.0% (196/265) of participants were still engaging with the app.At 4 weeks post quit date, 44.5% (118/265) of participants in the treatment arm had not smoked in the preceding 7 days compared with 28.7% (76/265) in the control group (risk ratio 1.55, 95% CI 1.23-1.96; P<.001; intention-to-treat, n=530).Self-reported 7-day abstinence agreed with carbon monoxide measurement (carbon monoxide <10 ppm) in 96% of cases (80/83) where carbon monoxide readings were available.No harmful effects of the intervention were observed.Conclusions The Quit Genius digital therapeutic intervention is a superior treatment in achieving smoking cessation 4 weeks post quit date compared with very brief advice.
