Efficacy of a Web-Based Intervention for Depressive Disorders: Three-Arm Randomized Controlled Trial Comparing Guided and Unguided Self-Help With Waitlist Control (Preprint)

Abstract

BACKGROUND Digital health applications are efficacious treatment options for mild-to-moderate depressive disorders. However, the extent to which psychological guidance increases the efficacy of these applications is controversial. OBJECTIVE We evaluated the efficacy of the online intervention “Selfapy” for unipolar depression. We also investigated differences between a psychotherapist-guided vs. unguided version compared with those from a control group. METHODS A cohort of 401 participants with mild-to-severe depressive disorders were assigned randomly to either participate in a guided version of Selfapy (involving weekly telephone calls of 25-minute duration), an unguided version of Selfapy, or to the waiting list (control group). Selfapy is a cognitive behavioral therapy-based intervention for depressive disorders of duration 12 weeks. Symptom assessment was undertaken at T1 (before study entrance), T2 (after 6 weeks), T3 (post-treatment, after 12 weeks), and T4 (follow-up, after 6 months). The main outcome was reduction in depressive symptoms in the Beck Depression Inventory (BDI-II) from T1 to T3. Secondary-outcome parameters were the Quick Inventory of Depressive Symptomatology – Self Report (QIDS-SR 16) and Beck Anxiety Inventory (BAI). RESULTS A total of 297 out of 401 participants (74.06%) completed the post-measurement at T3. In the ITT-analysis, both intervention groups showed a significantly higher reduction in depressive symptoms (BDI-II) from T1 to T3 compared with the control group, with high within-group effect sizes (guided: d = 1.46; unguided: d = 1.36). No significant differences were found for guided vs. unguided treatment groups. The response rate (BDI-II) was 46.4% for the guided version, 40.0% for the unguided version, and 2.0% in the control group. After 6 months (T4), treatment effects could be maintained for both intervention groups (BDI-II) without differences between either intervention group. CONCLUSIONS Selfapy can help to reduce depressive symptoms in guided or unguided versions. Follow-up data suggest that these effects could be maintained. The guided version was not superior to the unguided version. CLINICALTRIAL Current Controlled Trial DRKS00017191; Date of registration: 14 May 2019. INTERNATIONAL REGISTERED REPORT RR2-10.1186/s13063-021-05218-4