A randomized controlled trial testing the effects of sequential psychotherapy in depression: Changing therapist, or both therapist and method?

Background This study examined the effectiveness of sequential psychotherapy strategies for adults with major depressive disorder who did not respond to an initial course of cognitive behavioural therapy (CBT) or short-term psychodynamic supportive psychotherapy (SPSP). Methods In this randomized controlled trial, conducted in specialized mental health care in the Netherlands, from 185 non-responders from an initial 16-session treatment phase, 163 were randomly assigned 1:1:1 to one of three conditions: continuing treatment with the same therapist, switching to a different therapist, or switching both therapist and treatment method. All participants were offered an additional 16 sessions over eight weeks. The primary outcome was depressive symptom severity, measured using the Inventory of Depressive Symptomatology – Self Report (IDS-SR) in the intention-to-treat sample. Results All groups showed a modest but statistically significant reduction in depressive symptoms after the second treatment phase (mean change −5.23, 95 % CI -7.27 to −3.12, Cohen's d = 0.29). However, no significant differences in symptom reduction, response, or remission rates were found between the three treatment strategies. Conclusions Continuing psychotherapy after initial non-response leads to modest improvements in depressive symptoms. Switching therapist or both therapist and method does not appear to offer additional benefit, but also does not hinder outcomes. These findings suggest that there is no one-size-fits-all switching strategy that is suitable for all non-responders. Trial registration Both phases of the study were approved by the medical ethics committee of Medical Centre Leeuwarden (METC: RTPO970, registration number NL 56047.099.16, July 21th 2016) and the trial was registered with the Netherlands Trial Register (NL5753).