title: Using logistic regression modeling to predict sexual recidivism: the Minnesota Sex Offender Screening Tool-3 (MnSOST-3).
abstract: This study presents the results from efforts to revise the Minnesota Sex Offender Screening Tool-Revised (MnSOST-R), one of the most widely used sex offender risk-assessment tools. The updated instrument, the MnSOST-3, contains nine individual items, six of which are new. The population for this study consisted of the cross-validation sample for the MnSOST-R (N = 220) and a contemporary sample of 2,315 sex offenders released from Minnesota prisons between 2003 and 2006. To score and select items for the MnSOST-3, we used predicted probabilities generated from a multiple logistic regression model. We used bootstrap resampling to not only refine our selection of predictors but also internally validate the model. The results indicate the MnSOST-3 has a relatively high level of predictive discrimination, as evidenced by an apparent AUC of .821 and an optimism-corrected AUC of .796. The findings show the MnSOST-3 is well calibrated with actual recidivism rates for all but the highest risk offenders. Although estimating a penalized maximum likelihood model did not improve the overall calibration, the results suggest the MnSOST-3 may still be useful in helping identify high-risk offenders whose sexual recidivism risk exceeds 50%. Results from an interrater reliability assessment indicate the instrument, which is scored in a Microsoft Excel application, has an adequate degree of consistency across raters (ICC = .83 for both consistency and absolute agreement).
authors.affiliation: Minnesota Department of Corrections, St. Paul, MN, USA. grant.duwe@state.mn.us
authors.forename: Grant
authors.initials: G
authors.lastname: Duwe
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Freske
mesh_terms: D006801:Humans; D016015:Logistic Models; D008910:Minnesota; D011581:Psychological Tests / Q000592:standards*; D015203:Reproducibility of Results; D018570:Risk Assessment / Q000379:methods / Q000592:standards*; D055502:Secondary Prevention; D012742:Sex Offenses / Q000517:prevention & control