Understanding change in psychological treatments for depressive symptoms: The individual matters

Depressive symptoms may negatively affect normal functioning in daily life. Although effective psychological treatments are available for depressive symptoms, not all individuals may benefit from these treatments. There is a lack of knowledge on why and under which circumstances depressive symptoms improve in psychological treatments. This thesis focusses on studying predictors of depressive symptom change in cognitive behavioral therapy (CBT) and mindfulness-based treatments. The results supported the idea that increasing awareness of one’s present-moment experiences without judging them (i.e., mindfulness) improves one’s mood; on average, daily increases in mindfulness preceded rather than followed daily improvements in mood. Furthermore, individuals were more mindful on days that they performed a meditation or yoga exercise. Besides the role of mindfulness-skills, this thesis shows that diabetic patients with comorbid depressive symptoms benefit more from CBT and mindfulness-based treatments when they hold more positive expectations of treatment outcomes. Patients with higher expectations might be more involved in treatment since those patients were more likely to complete treatment and performed more homework in mindfulness-based treatments. In another study, it was shown that mutual agreement on treatment goals and tasks as well as the bond between the patient and the therapist predict depressive symptom change in CBT, but not in mindfulness-based treatment. The thesis shows that it is important to train specific skills in psychological treatments, that the extent to which these skills are beneficial differs between individuals, and that the effectiveness of psychological treatments depends on the care-recipient.