Abstract
BACKGROUND: Transdiagnostic interventions targeting shared mechanisms may improve treatment of mental health disorders. One way of providing such interventions is through blended treatment. This study examined the addition of an internet-based emotion regulation intervention to face-to-face psychotherapy in an outpatient setting. METHODS: In a pilot randomized controlled trial, 70 patients with a range of diagnoses were assigned to an internet-based program targeting emotion regulation + treatment as usual (face-to-face psychotherapy; TAU) (n = 35) or TAU (n = 35). Assessments occurred at baseline, after six, and after 12 weeks and included measures of symptom severity, emotion regulation, and various intervention feasibility parameters. RESULTS: ITT-analyses revealed no significant group-by-time interaction for the primary and almost all secondary outcomes. Descriptively, between-group effect sizes were in favor of the intervention group for almost all outcomes. Sensitivity analysis with patients who completed a minimum of three modules of the internet-based program showed a significant group-by-time interaction for the Difficulties in Emotion Regulation Scale in favor of the intervention group. The internet-based intervention showed good satisfaction ratings, user experience and usability. Findings from therapist measures complemented patient measures. CONCLUSION: Preliminary results show that an internet-based emotion regulation intervention added to psychotherapy may not reduce symptom severity compared to psychotherapy alone. The intervention was rated positively by patients and therapists regarding several parameters, but certain features still need to be improved. An RCT powered to detect small between-group effect-sizes is necessary to consolidate findings.