The predictive validity of the Dutch risk assessment instrument HKT-30 was investigated with a quasi-prospective design in a sample of habitual offenders with a substance use disorder (SUD). The study is reported according to RAGEE guidelines. The HKT-30 is an extension of the HCR-20. Files of 89 patients were coded and recidivism data were requested from the Ministry of Justice. Total scale scores and scores of the Clinical and Future scales were significantly predictive of recidivism for 1 and 2 years of time at risk, respectively. In contrast to earlier studies into recidivism, the H-scale had no predictive value. Regression analysis showed that the Clinical and Future scales contributed to the explanation of variance in recidivism, but not independently from each other. The conclusion is that the HKT-30 is a useful instrument for discovering risk factors and predicting recidivism for the population of habitual offenders with an SUD.

Sylvia Lammers, Lot Kokkelink, Hein deHaan
International Journal of Offender Therapy and Comparative Criminology, February 9, 2018