Does Reassessment Improve Prediction? A Prospective Study of the Sexual Offender Treatment Intervention and Progress Scale (SOTIPS)

Abstract

This prospective study examined the predictive validity of the Sex Offender Treatment Intervention and Progress Scale (SOTIPS; McGrath et al., 2012), a sexual recidivism risk/need tool designed to identify dynamic (changeable) risk factors relevant to supervision and treatment. The SOTIPS risk tool was scored by probation officers at two sites (n = 565) for three time points: near the start of community supervision, at 6 months, and then at 12 months. Given that conventions for analyzing dynamic prediction studies have yet to be established, one of the goals of the current paper was to demonstrate promising statistical approaches for the analysis of longitudinal studies in corrections. In most analyses, static SOTIPS scores predicted all types of recidivism (sexual, violent, and general [any]). Dynamic SOTIPS scores, however, only improved the prediction of general recidivism, and only when the analyses with the greatest statistical power were used (Cox regression with time dependent covariates).