Depression is a common mental illness which is costly for both society and for those affected. There is a need for effective treatments of depression and there is a need to make sure that the treatments that are given are based on scientific findings. In this study the investigators want to examine and compare two common treatment models for depression - Cognitive Behavioral Therapy and Emotion-Focused Therapy. The investigators want to investigate what characterizes these treatments when they are successful, and seek to better understand what it is like for patients to receive these treatments. Also, the investigators will investigate the experience of patients who abruptly discontinue treatment. To investigate these questions, self-report measures, interviews and analysis of session recordings will be used.

Depression is a widespread mental disorder which can result in severe impairment and reduced quality of life for those affected. Cognitive behavioral therapy (CBT) is the approach with strongest empirical support, and is often recommended as treatment for depression, as in the NICE Guidelines for Depression from 2009. However, research indicates that not all patients respond to CBT, indicating a need to expand the range of available evidence-based psychotherapies, and mapping the mechanisms of change in existing treatments.

Emotion focused therapy (EFT) is one promising treatment for depression with empirical support for its efficacy. A previous study found equal outcome in CBT and Process-Experiential treatment/EFT for depression, but more studies are needed to replicate these findings across cultural contexts. The main aim of this study is to investigate whether there are significant differences in the therapeutic effect of EFT compared to that of CBT for patients with moderate and major depressive disorder in a Norwegian outpatient setting.

Although several psychotherapeutic approaches have shown efficacy in the treatment of depression, no psychotherapeutic interventions is beneficial for all patients. There is a need for research that investigates what treatments works for whom, based on patient characteristics and preferences. The present study will investigate whether patient characteristics moderate treatment outcome, both within and between treatment conditions. In addition, qualitative interviews will be conducted to get a deeper understanding of what clients find helpful and challenging within the CBT and EFT condition, and to explore the experience of patients who drop-out of the treatment process.

In order to further develop psychotherapeutic treatments and increase their effectiveness, there is a need to identify processes that are related to good and poor outcome. Process-outcome studies are commonly used for this purpose. The present study will investigate and compare characteristics of psychotherapy processes in both the CBT and EFT conditions and how these are related to outcome.

Study design and Method

The study will be conducted as a randomized controlled trial (RCT) in order to compare the efficacy of EFT to CBT. RCT's are considered the gold standard for efficacy studies. Participants will be recruited from the Norwegian mental health program "Return to work", a publicly funded treatment program where patients with common mental health issues receives outpatient psychotherapeutic treatment to reduce and prevent sick leave.

The present study will address the following research hypothesis and questions:

1. EFT and CBT will not result in significantly different outcome in the treatment of patients with moderate and major depressive disorder.
2. Patient characteristics (severity of depression, adverse childhood experiences and clients' initial ability to make sense of their experience) will moderate treatment outcome for both conditions.
3. Will therapeutic processes (therapeutic alliance, therapist empathy, clients' ability to make sense of their experience and emotional processing) mediate treatment outcome equally for both conditions?
4. What do patients in both conditions describe as helpful and unhelpful aspects of treatment?
5. How do patients in both conditions describe their own change or lack or change after treatment?
6. How do patients that choose to drop out of treatment describe the processes leading to that decision?

Inclusion Criteria:

- Moderate or major depressive episode as primary diagnosis

Exclusion Criteria:

• Serious mental illness (schizophrenia, severe bipolar disorder, recent or current psychotic episode) or intellectual disability.
• Severe alcohol or drug abuse, last 12 months.
• Suicidality last 6 months
• Severe medical issues
• If the participant is on antidepressive medication, the dosage must have been stable for more than 4 weeks, and the participant must consent to staying on the same dosage for the duration of the treatment.
• The participant is currently in another treatment for depression