| Evaluation of the efficacy of psychological intervention depends on the ability to measure treatment outcomes with reliable and valid measures that draw from multiple perspectives. A treatment outcome measure that takes into account therapist perceptions could provide clinicians and researchers with additional data that are easily accessible and potentially complimentary to existing outcome measures and provide an alternative method to evaluate treatment progress. The Therapist Perception of Treatment Outcome (TPTO) was developed to assess therapist perceptions of indicators of treatment success within the context of Multisystemic Therapy (MST), a widely disseminated treatment for delinquent youth with substantial evidence of positive treatment outcomes (Henggeler & Schaeffer, 2010; Kazdin & Wassell, 1998).;Development of TPTO items included interviews with 9 MST therapists. The therapists provided their perspectives of factors that characterize families who are successful in treatment from those who are not. The salient themes from these qualitative interviews were then identified and used to create the 20-item measure. This study examined the reliability and validity of TPTO scores in the context of an ongoing NIMH-funded longitudinal study, conducted in community settings, assessing contributors to treatment success and failure with MST. Families who participated in this study had a youth with antisocial behavior problems. Therapists completed the TPTO for 111 families during mid-treatment, and 163 families at treatment termination.;Multilevel exploratory factor analyses provided evidence for a caregiver and youth scale. Rasch analyses were used to assess item and scale characteristics, dimensionality, category functioning, and to provide good evidence for internal consistency of total, caregiver, and youth scores during and at the end of treatment. In addition, multilevel analyses of temporal consistency, sensitivity to treatment effects, construct validity (correlations with related constructs), and discriminative validity supported the total, caregiver, and youth scale scores at the end of treatment and the total and youth scale scores at mid-treatment. Based on these analyses, there is strong evidence for future use of the TPTO as well as support for further use of therapists as raters of psychological treatment. |
