Randomized controlled trial (RCT) to test the superiority of blended cognitive behavioral therapy (bCBT) over standard CBT for unipolar depression in adults

Objectives: This study evaluates the medical benefits of a blended cognitive behavioral therapy (bCBT) program consisting of standard cognitive behavioral therapy (CBT) and a digital health application (elona therapy), compared to standard CBT for unipolar depression in adult patients in outpatient psychotherapy.Trial design: A multicenter, randomized, two-arm controlled trial.Methods: A total of 283 adult patients diagnosed with unipolar depression were recruited from psychotherapy practices across Germany and randomized in a 1:1 ratio to receive either standard CBT with the “elona therapy” digital health application (bCBT group) or standard CBT alone (treatment as usual; TAU). Over 12 weeks, we assessed symptoms of depression and anxiety, quality of life, perceived self-efficacy, depression literacy, treatment adherence, overall disease severity and improvement using standardized questionnaires at baseline (T0) and post-intervention (T1). We hypothesized that the bCBT group would show greater improvements across these domains compared to the TAU group. Participants were unaware of the study objective and were provided the information that the study investigates the optimal timing of the addition of a digital intervention.Results: Patients in the bCBT group improved their symptoms of depression (primary outcome), anxiety, quality of life, perceived self efficacy, depression literacy and overall disease severity significantly better than the TAU group over 12 weeks of treatment. Patients in the bCBT group had significantly higher treatment adherence, evidenced by higher scores in patient- and therapist-rated adherence questionnaires, as well as lower drop-out rates and higher session attendance compared to TAU. The number of adverse events was low, and no more adverse events were reported in the bCBT group than the TAU group.Conclusions: Results of this trial provide comprehensive evidence of the medical benefits of the bCBT program supported by elona therapy compared to the standard CBT treatment. bCBT with elona therapy appears to be a safe treatment option.