Understanding the influence of outcome expectations on attendance, dropout and clinical outcomes in psychotherapy

Outcome expectations are beliefs patients hold about the consequences of engaging in psychological treatment. They exist on a continuum from positive beliefs that treatment will be helpful, to beliefs that treatment will have negative consequences. Evidence-to-date suggests that more optimistic outcome expectations are associated with improved clinical outcomes. This thesis aimed to explore the association between outcome expectations, attendance in therapy, dropout and clinical outcomes.

Firstly, a systematic review of the literature was conducted to answer the question of whether the therapeutic alliance mediates the association between outcome expectations and clinical outcomes. Ten studies met the inclusion criteria and were included in the review. A narrative synthesis of studies was conducted and found that the therapeutic alliance partially mediates the association between outcome expectations and clinical outcomes. Findings suggest that more optimistic outcome expectations facilitate a stronger therapeutic alliance, which in turn contributes to patients experiencing improved outcomes. Current evidence suggests the alliance does not fully mediate this association, indicating other mediator variables are involved.

Secondly, an empirical study was conducted to investigate whether pre-treatment outcome expectations predict attendance at subsequent psychological therapy appointments and dropout from therapy. Investigations were undertaken to determine whether variability in patient pre-treatment expectancy is attributable to the assessing therapist after controlling for patients’ characteristics. Results found that patients’ outcome expectations assessed at an initial (pre-treatment) assessment appointment significantly predicted attendance at the first therapy session when controlling for the effect of the assessing therapist. Contrastingly, pre-treatment outcome expectations did not predict subsequent dropout from treatment. There was significant variability in patient outcome expectations across assessing therapists after controlling for patients’ characteristics. Results suggest that individual therapists influence patient outcome expectations after one initial assessment and this has a subsequent impact on patient attendance in therapy.