Measuring homework utility in psychotherapy: Cognitive-behavioral therapy for adult attention-deficit hyperactivity disorder as an example

Homework, or practice of skills learned in treatment, is a critical component of cognitive-behavioral therapy (CBT). However, no matter how much effort clients put into their therapy homework, this effort can only be useful if adherence to homework is related to improvement in symptoms. Although homework adherence (the extent to which clients practice skills learned in therapy outside of sessions) has been studied with respect to psychotherapy outcomes, 'homework utility', a potentially important mechanism of action in cognitive behavioral treatments, has yet to be operationally defined as a distinct construct, and it has yet to be studied with respect to psychotherapy outcome. We therefore propose an operational definition of therapy homework utility: the extent to which homework adherence is associated with parallel symptom improvement across time throughout treatment for each individual client. In this capacity, an indicator of homework utility is operationalized as the within subject correlation of session-by-session homework adherence with session-by-session symptom change. We used a sample of clients who underwent CBT for attention-deficit hyperactivity disorder in adulthood as an example to quantify homework utility and examine its association to treatment outcome. Consistent with our hypotheses, homework utility was significantly associated with overall therapy outcome. Homework utility may be an important construct relevant to the mechanism of action of structured psychotherapies, and examining within subject sessions-by-session correlations with symptomatic change may be a useful way to examine other psychotherapy process variables.