Long-term predictive validity of the risk matrix 2000: a comparison with the static-99 and the sex offender risk...

The purpose of this study is to examine the predictive accuracy of the Risk Matrix 2000 on an independent sample of 351 sexual offenders, followed in the community for an average duration of 11.4 years (range 0-20 years, SD = 4.4 years). For comparison purposes, this study also examines the predictive accuracy of two other risk assessment instruments, specifically modified versions of the Static-99 and the Sex Offender Risk Appraisal Guide (SORAG). Results indicate that the Risk Matrix 2000 demonstrates convergent validity by correlating with the other risk assessment instruments. Moreover, the Risk Matrix 2000 is predictive of recidivism above chance levels, exhibiting medium to large effect sizes, although in general, the other two instruments, particularly the SORAG, are superior. Results also indicate differences in predictive validity when comparing 2-year, 5-year, and variable follow-up periods. Finally, a cumulative meta-analysis compares and integrates current findings with those obtained from the accumulation of previous studies, and new cumulative estimates are provided.