The Treatment Engagement Rating scale (TER) for forensic outpatient treatment: Description, psychometric properties, and norms

The Treatment Engagement Rating scale (TER) is a Dutch therapist rating instrument for treatment engagement (TE) of forensic outpatients. It yields scores for nine components of TE, which are aggregated in a total score. Following an analysis of the concept of TE, the TER is described, and various psychometric analyses of data from a forensic outpatient sample are reported. The nine component scores were found to constitute a homogeneous scale with good internal consistency (alpha=0.93, n=328) and adequate inter-rater reliability (intraclass correlation coefficient (ICC)=0.76, n=99). The validity of the TER is supported by correlations of 0.47, 0.66, and 0.91 (n=328) with measures for the motivation to engage in treatment. Applications for the TER in clinical practice and research are suggested.