Efficacy of digital cognitive behavioral therapy for moderate‐to‐severe symptoms of generalized anxiety disorder: A randomized controlled trial

Background Cognitive behavioral therapy (CBT) is an efficacious intervention for generalized anxiety disorder (GAD). Digital CBT may provide a scalable means of delivering CBT at a population level. We investigated the efficacy of a novel digital CBT program in those with GAD for outcomes of anxiety, worry, depressive symptoms, sleep difficulty, wellbeing, and participant‐specific quality of life. Methods This online, two‐arm parallel‐group superiority randomized controlled trial compared digital CBT with waitlist control in 256 participants with moderate‐to‐severe symptoms of GAD. Digital CBT (Daylight), was delivered using participants’ own smartphones. Online assessments took place at baseline (Week 0; immediately preceding randomization), mid‐intervention (Week 3; from randomization), post‐intervention (Week 6; primary endpoint), and follow‐up (Week 10). Results Overall, 256 participants were randomized and intention‐to‐treat analysis found Daylight reduced symptoms of anxiety compared with waitlist control at post‐intervention, reflecting a large effect size (adjusted difference [95% CI]: 3.22 [2.14, 4.31], d = 1.08). Significant improvements were found for measures of worry; depressive symptoms, sleep difficulty, wellbeing, and participant‐specific quality of life. Conclusion Digital CBT (Daylight) appears to be safe and efficacious for symptoms of anxiety, worry, and further measures of mental health compared with waitlist control in individuals with GAD.