TY - JOUR AU - Garvert, Mona M AU - McFadyen, Jessica AU - Linke, Stuart AU - McCloud, Tayla AU - Meyer, Sofie S AU - Sobanska, Sandra AU - Sharp, Paul B AU - Long, Alex AU - Huys, Quentin J M AU - Ahmadi, Mandana PY - 2025 DA - 2025/4/10 TI - Safety and Efficacy of Modular Digital Psychotherapy for Social Anxiety: Randomized Controlled Trial JO - J Med Internet Res SP - e64138 VL - 27 KW - social anxiety disorder KW - randomized controlled trial KW - digital mental health KW - cognitive behavioral therapy KW - internet-delivered CBT AB - Background: Social anxiety disorder is a common mental health condition characterized by an intense fear of social situations that can lead to significant impairment in daily life. Cognitive behavioral therapy (CBT) has been recognized as an effective treatment; however, access to therapists is limited, and the fear of interacting with therapists can delay treatment seeking. Furthermore, not all individuals respond. Tailoring modular treatments to individual cognitive profiles may improve efficacy. We developed a novel digital adaptation of CBT for social anxiety that is both modular and fully digital without a therapist in the loop and implemented it in the smartphone app Alena. Objective: This study aimed to evaluate the safety, acceptability, and efficacy of the new treatment in online participants with symptoms of social anxiety. Methods: In total, 2 web-based randomized controlled trials (RCTs) comparing individuals with access to the treatment through the app to a waitlist control group were conducted. Participants were recruited on the web and reported Social Phobia Inventory (SPIN) total scores of ≥30. Primary outcomes were safety and efficacy over 6 weeks in 102 women aged 18 to 35 years (RCT 1) and symptom reduction (SPIN scores) after 8 weeks in 248 men and women aged 18 to 75 years (RCT 2). Results: In RCT 1, active and control arm adverse event frequency and severity were not distinguishable (intervention: 7/52, 13%; waitlist control: 8/50, 16%; χ21=0.007; P=.93). App acceptability was high, with a median completion rate of 90.91% (IQR 54.55%-100%). Secondary outcomes suggested greater symptom reduction in the active arm (mean SPIN score reduction −9.83, SD 12.80) than in the control arm (mean SPIN score reduction −4.13, SD 11.59; t90=−2.23; false discovery rate P=.04; Cohen d=0.47). RCT 2 replicated these findings. Adverse event frequency was comparable across the 2 groups (intervention: 20/124, 16.1%; waitlist control: 21/124, 16.8%; χ21<0.001; P>.99). Despite a longer treatment program, median completion remained high (84.85%, IQR 51.52%-96.97%). SPIN score reduction was greater in the active arm (mean −12.89, SD 13.87) than in the control arm (mean −7.48, SD 12.24; t227=−3.13; false discovery rate P=.008; Cohen d=0.42). Conclusions: The web-only, modular social anxiety CBT program appeared safe, acceptable, and efficacious in 2 independent RCTs on online patient groups with self-reported symptoms of social anxiety. Trial Registration: ClinicalTrials.gov NCT05858294; https://clinicaltrials.gov/study/NCT05858294 (RCT 1) and ClinicalTrials.gov NCT05987969; https://clinicaltrials.gov/study/NCT05987969 (RCT 2) SN - 1438-8871 UR - https://www.jmir.org/2025/1/e64138 UR - https://doi.org/10.2196/64138 UR - http://www.ncbi.nlm.nih.gov/pubmed/40208666 DO - 10.2196/64138 ID - info:doi/10.2196/64138 ER -