A self-guided mobile app for symptoms of depression in adolescents: results of a randomized controlled trial (Preprint)
Year: 2026
Type: preprint
Study designs: Randomized Controlled Trial, Clinical Trial
Abstract: BACKGROUND Adolescent depression is a severe public health crisis exacerbated by extreme provider shortages and structural barriers to care. Self-guided digital therapeutics based on evidence-based psychotherapy offer a potentially scalable solution to bridge this expanding treatment gap, yet robust clinical trial evidence demonstrating their efficacy remains limited. OBJECTIVE This study aimed to evaluate the efficacy and safety of Spark, a 5-week, self-guided smartphone application based on behavioral activation protocols, as an adjunct treatment for symptoms of depression in adolescents and young adults. METHODS We conducted a decentralized, parallel-group, single-blind (investigator) randomized controlled trial across the United States. Participants aged 13–21 years with self-reported depression symptoms (8-item Patient Health Questionnaire [PHQ-8] score ≥ 5) under the care of a licensed healthcare provider were recruited online. They were randomized (1:1) to either the treatment arm (Spark app) or an active control arm (assessment-enhanced usual care [eUC] via a control app) for 5 weeks. Randomization was stratified by baseline severity and medication status. The primary outcome was depressive symptom severity measured via total PHQ-8 score at the post-intervention time point (week 5), analyzed using mixed-effects models for repeated measures (MMRM) in the intention-to-treat (ITT) population. Secondary outcomes included treatment response, remission, and 1-month follow-up durability. RESULTS The Spark group showed significantly greater reductions in depression symptoms compared to the control group at both the end of the intervention (p<0.001) and at the one-month follow-up (p=0.008). Spark participants were also nearly three times more likely to achieve treatment response (31.7% vs 11.6%), remission (24.9% vs 9.4%), and a minimal clinically important difference (40.5% vs 15.8%). Clinical benefits were consistent across age, baseline severity, and concurrent antidepressant use subgroups. The intervention was well-tolerated with no significant safety concerns, and fewer adverse events reported in the Spark arm (n=6) than in the usual care arm (n=16). CONCLUSIONS A self-guided, mobile app-based behavioral activation program is an effective, safe, and durable adjunct intervention for reducing depressive symptoms in adolescents. These findings support the deployment of validated digital therapeutics to provide immediate, scalable clinical care within a strained mental health infrastructure. CLINICALTRIAL ClinicalTrials.gov Registration Number: NCT05462652 https://clinicaltrials.gov INTERNATIONAL REGISTERED REPORT RR2-10.2196/48740
Language: English
Subfield: Applied Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7165355343