Age and Sex Offense/Violent Offense
The risk of sexual recidivism declines with advancing age. Actuarials which are not stratified underestimate risk for younger offenders and overestimate risk for older offenders.
Recent research (n = 9,305) underscores the importance of using age-stratified actuarial tables in sex offender risk assessments.
Wallert, R., Cramer, E., Waggoner, J., Skelton, A., and Vess, J. (December, 2010).
Sex Abuse. 22: 471-490,
Abstract
A useful understanding of the relationship between age, actuarial scores, and sexual recidivism can be obtained by comparing the entries in equivalent cells from “agestratified” actuarial tables. This article reports the compilation of the first multisample age-stratified table of sexual recidivism rates, referred to as the “multisample age-stratified table of sexual recidivism rates (MATS-1),” from recent research on Static- 99 and another actuarial known as the Automated Sexual Recidivism Scale. The MATS-1 validates the “age invariance effect” that the risk of sexual recidivism declines with advancing age and shows that age- restricted tables underestimate risk for younger offenders and overestimate risk for older offenders. Based on data from more than 9,000 sex offenders, our conclusion is that evaluators should report recidivism estimates from age-stratified tables when they are assessing sexual recidivism risk, particularly when evaluating the aging sex offender.
Improving the predictive accuracy of static-99 and static-2002 with older sex offenders.
Helmus, L., Thornton, D., Hanson, R.K., Babchishin, K.M., (Feb. 2012).
Sex Abuse, vol. 24, no. 1, 64-101.
Abstract
Actuarial risk assessment scales and their associated recidivism estimates are generally developed on samples of offenders whose average age is well below 50 years. Criminal behavior of all types declines with age; consequently, actuarial scales tend to overestimate recidivism for older offenders. The current study aimed to develop a revised scoring system for two risk assessment tools (Static-99 and Static-2002) that would more accurately describe older offenders’ risk of recidivism. Using data from 8,390 sex offenders derived from 24 separate samples, age was found to add incremental predictive validity to both Static-99 and Static-2002. After creating new age weights, the resulting instruments (Static-99R and Static- 2002R) had only slightly higher relative predictive accuracy. The absolute recidivism estimates, however, provided a substantially better fit for older offenders than the recidivism estimates from the original scales. We encourage evaluators to adopt the revised scales with the new age weights.
Less is more: Using Static-2002R subscales to predict violent and general recidivism among sexual offenders.
Babchishin, Kelly M., Hanson, R. Karl., Blais, Julie.
Sexual Abuse: Journal of Research and Treatment, Vol 28(3), Apr, 2016. pp. 187-217.
Abstract:
Given that sexual offenders are more likely to reoffend with a nonsexual offense than a sexual offense, it is useful to have risk scales that predict general recidivism among sexual offenders. In the current study, we examined the extent to which two commonly used risk scales for sexual offenders (Static-99R and Static-2002R) predict violent and general recidivism, and whether it would be possible to improve predictive accuracy for these outcomes by revising their items. Based on an aggregated sample of 3,536 adult male sex offenders from Canada, the United States, and Europe (average age of 39 years), we found that a scale created from the Age at Release item and the General Criminality subscale of Static-2002R predicted nonsexual violent, any violent, and general recidivism significantly better than Static-99R or Static-2002R total scores. The convergent validity of this new scale (Brief Assessment of Recidivism Risk–2002R [BARR-2002R]) was examined in a new, independent data set of Canadian high-risk adult male sex offenders (N = 360) where it was found to be highly correlated with other risk assessment tools for general recidivism and the Psychopathy Checklist–Revised (PCL-R), as well as demonstrated similar discrimination and calibration as in the development sample. Instead of using total scores from the Static-99R or Static-2002R, we recommend that evaluators use the BARR-2002R for predicting violent and general recidivism among sex offenders, and for screening for the psychological dimension of antisocial orientation.