The validity of the Iowa Sex Offender Risk Assessment for predicting recidivism in female sexual offender

The purpose of this study was to determine the validity of the Iowa Sex Offender Risk Assessment (ISORA) instrument used in the Iowa Department of Corrections to assess for future occurrences of female offender recidivism. Using a sample of 105 females convicted of a sexual offense in the State of Iowa, the current study examined rates of recidivism using the ISORA. The goal of this study was to determine the validity of the ISORA in predicting recidivism rates as measured by (a) new convictions for sex offenses and other violent crimes, (b) new convictions for sex crimes using a strict definition, and (c) any new conviction for any new crime. Data were collected on all female participants in this study using case file information from various database resources. Mean-cost rating scores and Receiver Operating Characteristic Curve analyses were conducted to explore the relationships between risk assessment categories on the ISORA and each type of recidivism as well as between raw ISORA scores and each type of recidivism. Results showed the overall recidivism rate of female offenders was 22% for this study, while the sexual recidivism rate in this study was 2%. Results also provided evidence that the ISORA can be used to predict sexual and violent recidivism (AUC = .85) as well as general recidivism (AUC = .64) for female sex offenders. In conclusion, the ISORA is a valid risk assessment tool when predicting general and sexual or violent recidivism for female sexual offenders. However, further research examining improvements in the instrument could be conducted to enhance the validity of the instrument.