Clients' and therapists' experiences of five general change mechanisms during an Internet-based cognitive behavioral intervention for family caregivers.

Objectives: Despite its efficacy, little is known about what makes Internet-based cognitive behavioral therapy (iCBT) effective. We, therefore, analyze participants' and therapists' experiences of Grawe's five general change mechanisms (alliance, resource activation, clarification, problem actuation, mastery) during an iCBT intervention for family dementia caregivers, and how their experiences were related to treatment outcomes.

Method: Participants (N = 30) exchanged eight weekly messages with a therapist via an Internet platform. We used the Bern Post Session Report to assess participants' and therapists' experiences of the general change mechanisms after each session.

Results: Treatment outcomes were associated with therapists' overall experiences of alliance, clarification, and mastery. Participants experienced more problem actuation than therapists. Only participants' and therapists' experiences of clarification over time differed.

Conclusions: Grawe's general change mechanisms are also relevant for iCBT. We recommend considering Grawe's framework when designing Internet-based therapeutic interventions and when training therapists to deliver such interventions.