title: Is more better? Combining actuarial risk scales to predict recidivism among adult sex offenders.
abstract: The present study was conducted to determine whether combining the results of multiple actuarial risk scales increases accuracy in predicting sex offender recidivism. Multiple methods of combining 4 validated actuarial risk scales--the Violence Risk Appraisal Guide, the Sex Offender Risk Appraisal Guide, the Rapid Risk Assessment for Sexual Offense Recidivism, and the Static-99--were evaluated in a sample of 215 adult male sex offenders. These included the intuitively appealing believe-the-negative and believe-the-positive rules, adapted from medical decision making; the combination of absolute decision thresholds across a range of cutoff scores; and the statistical optimization methods of logistic regression and principal components analyses. No combination method provided a statistically significant or consistent advantage over the predictive accuracy of the single best actuarial scale.
authors: Law and Mental Health Program, Centre for Addiction and Mental Health, Toronto, Ontario, Canada. Michael_Seto@camh.net
authors: Michael C
authors: MC
authors: Seto
mesh_terms: D000328:Adult; D003657:Decision Making; D006801:Humans; D016015:Logistic Models; D008297:Male; D008960:Models, Psychological; D012372:ROC Curve; D012008:Recurrence; D012307:Risk Factors; D012742:Sex Offenses / Q000706:statistics & numerical data*; D011795:Surveys and Questionnaires; D013997:Time Factors