Building evidence on digital psychotherapies for adults living with depression: a systematic scoping review of populations, interventions and design features of ongoing and planned randomised controlled trials.

Abstract

BACKGROUND Digital psychotherapies may offer scalable options for depression, but most randomised controlled trials (RCTs) are at moderate or high risk of bias. Mapping the methodologies, populations, interventions and outcomes of completed, ongoing and terminated/withdrawn RCTs of digital psychotherapies for depression could help anticipate future evidence gaps and redundancies. STUDY SELECTION AND ANALYSIS We conducted a systematic scoping review of RCTs registered in the WHO International Clinical Trials Registry Platform, ClinicalTrials.gov, European Union Clinical Trials Register and European Union Clinical Trials Information System between 2018 and 2025. Eligible RCTs evaluated digital psychotherapies for adults with depressive disorders, bipolar depression or depressive symptoms. Extracted data encompass methodological features, population characteristics, settings, description of intervention, control, funders, registration timing and reporting practices. FINDINGS Among the 681 RCTs, 51.8% were completed, 34.1% published their results, 78.1% were prospectively registered and 8.5% were industry funded. Multicentre RCTs accounted for 23.1%, with 42.9% being planned in the USA, Germany or Canada and 25.1% recruiting in low- or middle-income countries. Inclusion relied on self-reported symptoms only for 61.5% and suicidal ideation was an exclusion criterion in 61.8%. The most frequent type of digital psychotherapy was cognitive-behavioural therapy for 64.6%. Human support was a component of the intervention in 44.2%. Chatbots were assessed by 4.6%. Waitlist control was used in 21%, with 49.3% of RCTs being open-label. The most frequent primary outcome was the Patient Health Questionnaire-9 for 35.7%. CONCLUSION Strengthening future evidence on digital psychotherapies requires timely dissemination of results, use of active controls, diversifying assessed psychotherapies and studying efficacy in populations with limited access to psychotherapy.