Who defines improvement? Patients' global reports of improvement compared to standardized measures of improvement in cognitive processing therapy for posttraumatic stress disorder.

Standardized measures have typically been used to assess symptom change during treatment in psychological research and practice. However, standardized measures may not fully capture patients' experiences of therapeutic change. Patients' global reports of their improvement during treatment across domains of symptoms and functioning are also important and may provide distinct information from standardized measures. The current study compared both types of patient reports of improvement during cognitive processing therapy (CPT) for posttraumatic stress disorder (PTSD). We also examined process-level predictors of improvement assessed using both methods. Participants were 254 adult survivors of interpersonal violence receiving CPT. Patients' global reports of improvement in each domain (PTSD symptoms, relationships, health concerns, sexual functioning, school/work performance, and life satisfaction), each rated on a Likert scale via the Treatment Outcome Questionnaire, were significantly correlated with the corresponding standardized measure of improvement in the same domain, with most effect sizes in the small-to-medium range. Patients' perceptions of the therapy (helpfulness, likability) significantly predicted both global ratings and standardized measures of improvement, while patients' perceptions of the therapeutic relationship, patients' perceptions of barriers to therapy attendance, and objective indices of attendance did not predict improvement. Results highlight the importance of patients' experiences with treatment and suggest that assessing patients' global ratings of their improvement during treatment provides distinct information from standardized measures of improvement, and both are important to include when measuring therapeutic change.