Mechanisms of Change in Psychotherapy (MOP)

Background: Major depressive disorder (MDD) is a prevalent psychiatric condition associated with significant disability, mortality and economic burden. MDD is ranked fourth in terms of disease burden as defined by the World Health Organization (2001). Cognitive Behavioral Therapy (CBT) and Psychodynamic Psychotherapy (PDT) are found to be equally effective for patients with depression. However, many patients do not respond sufficiently to treatment and relapse rates are high. To be able to offer individualized treatment, a clinically important question is therefore whether some patients profit more from one of the two therapies. At present little is known on which patient characteristics (moderators) may be associated with differential outcomes of CBT and PDT and through what kind of therapeutic processes and mechanisms (mediators) improvements occur in each therapy mode. There are actually only theoretical assumptions sparsely supported by research findings on what moderates and mediates the treatment effects of CBT and PDT. Aims: The overall aim of this project is to examine putative moderators and mediators in CBT and PDT and develop more basic knowledge about their impact on outcomes of psychotherapy for patients with MDD. Methods and study design: The study is a randomized clinical trial. One hundred patients will be randomized to one of two treatment conditions. The patients will be treated over 28 weeks with either CBT (one weekly session over 16 weeks and 3 booster sessions (monthly) during the rest of the 28 week study period) or PDT (one weekly session in 28 weeks). The patients will be evaluated at baseline, during therapy, at the end of therapy, and at follow-up investigations 1 and 3 years after treatment termination. The outcome measures comprise a large range of clinical and process variables, including assessment tools measuring specific preselected putative moderators and mediators. Discussion: The clinical outcome of this trial may guide clinicians to decide what kind of treatment should be offered the individual patient. Moreover, it will shed light on what kind of mechanisms in psychotherapy that is followed by symptom improvement and increased psychosocial functioning.

In this study we want to examine moderators and mediators in two equally effective, well known psychotherapeutic treatments (Psychodynamic and cognitive behavior therapy)

The included patients will receive cognitive therapy for depression for 16 weeks and monthly booster sessions up to 28 weeks.

In this study we want to compare CBT and PDT and examine whether some patients will benefit from CBT and other from PDT. More specifically we want to examine moderators and mediators for improvement in depressive symptoms in the two interventions arms.

Change in scores between baseline and 28 weeks (end of therapy) and change between baseline and one and three year follow-up

Change in scores between baseline and 28 weeks (end of therapy) and change between baseline and one and three year follow-up

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Change in scores during therapy and the follow-up periode (8 weeks, 16 weeks, 28 weeks, 1 year and 3 year follow up)

Inclusion Criteria: Patients aged between 18-65 years, with depressive disorder according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 2000) unipolar MDD diagnosis will be included.MINI plus (Sheehan et al., 1998 will be used as assessment tool. Comorbidity is expected to be frequent. Written consent will be obtained from all patients. The participants need to have the ability to speak and understand a Scandinavian language, and willingness and ability to give informed consent. Exclusion Criteria: Current or past neurological illness, traumatic brain injury, current alcohol and/or substance dependency disorders, psychotic disorders, developmental disorders, and mental retardation.

The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Malkomsen A, Rossberg JI, Dammen T, Wilberg T, Lovgren A, Ulberg R, Evensen J. How therapists in cognitive behavioral and psychodynamic therapy reflect upon the use of metaphors in therapy: a qualitative study. BMC Psychiatry. 2022 Jun 27;22(1):433. doi: 10.1186/s12888-022-04083-y.

Malkomsen A, Rossberg JI, Dammen T, Wilberg T, Lovgren A, Ulberg R, Evensen J. Digging down or scratching the surface: how patients use metaphors to describe their experiences of psychotherapy. BMC Psychiatry. 2021 Oct 27;21(1):533. doi: 10.1186/s12888-021-03551-1.

Rossberg JI, Evensen J, Dammen T, Wilberg T, Klungsoyr O, Jones M, Boen E, Egeland R, Breivik R, Lovgren A, Ulberg R. Mechanisms of change and heterogeneous treatment effects in psychodynamic and cognitive behavioural therapy for patients with depressive disorder: a randomized controlled trial. BMC Psychol. 2021 Jan 22;9(1):11. doi: 10.1186/s40359-021-00517-6.