Problem resolution scale: A single-item instrument for easily assessing clinical improvement.

This study describes the development and tests the validity of the Problem Resolution Scale (PRS)-a single-item measure developed by researchers at Systemic Practice Research Network (SYPRENE) for assessing the degree to which the focal problem of therapy is perceived as resolved. Data were collected at termination from 747 clients seen across 18 therapists. Results suggested good construct validity, supported by a strong correlation between client and therapist perceptions as assessed by the PRS (r = 0.71, p < 0.001). Good criterion validity was also supported by strong correlations between client-reported psychological well-being and functioning at termination and both client-reported (r = -0.63; p < 0.001) and therapist-reported (r = -0.66; p < 0.001) problem resolution scores. Linear mixed model regression and stratified correlation analysis controlling for the therapist and presenting problem effects confirmed criterion validity. Results provide initial evidence for the validity and utility of the PRS.