The assessment of dynamic risk and recidivism in a sample of special needs sexual offenders

Abstract

The predictive validity of four risk assessment instruments: the RRASOR, SVR-20, RM2000-V and the ARMIDILO-Stable and -Acute dynamic client subscales were assessed on a sample of 88 offenders: 44 mainstream and 44 sexual offenders with special needs, who had been matched on risk items within the RRASOR tool. Instruments were coded retrospectively from file information. Sexual reconviction data was used, in conjunction with sexual recidivism data based on unofficial data sources, over a mean follow-up period of 8.8 years. The results of this study found that the ARMIDILO instrument was the best predictor for sexual reconviction among offenders with special needs (ARMIDILO-Stable, AUC 00.60; ARMIDILO-Acute, AUC00.73), while the predictive validities of the RRASOR (AUC 00.53) and the RM2000-V (AUC 00.50) were little better than chance. In contrast, the SVR-20 yielded a higher score (AUC 00.73) for the non-ID sample, than for the intellectually disabled sample (AUC 00.45). Within the special needs group, the ARMIDILO-Acute, SVR-20 Psychosocial Affect, and Overall scales were better predictors of sexual recidivism for the intellectually disabled subgroup (AUCs ranging from 0.75 to 0.88). These results are discussed in the context of current practice.

Measurement of Change in Dynamic Factors Using the START: AV

“…The acute dynamic risk factors also significantly contributed to the prediction of recidivism, but yielded better predictive accuracy when averaged over a 6-month period, suggesting that the acute dynamic factors were more stable than anticipated (Hanson et al, 2007). However, the research on risk assessment in juvenile justice on acute and stable dynamic factors is scant; such investigations appear limited to adult sex offenders (Beech & Ward, 2004; Blacker, Beech, Wilcox, & Boer, 2011; Hanson & Harris, 2000; Hanson et al, 2007) or adult offender/parolee populations (Yesberg & Polaschek, 2015; Yesberg, Scanlon, Hanby, Serin, & Polaschek, 2015). …”

Intelligent Diagnosing of Intellectual Disabilities in Offenders: Food for Thought

“…Although probably most of the studies we have reviewed, did rely on full IQ testing, we observe a persistent lack of detailed assessment information to date. Returning to the aforementioned double special issue of Psychology, Crime & Law from 2011, it appears that none of seven empirical studies (Blacker, Beech, Wilcox, & Boer, 2011;Fitzgerald, Gray, Taylor, & Snowden, 2011;Holland & Perrson, 2011;Lindsay et al, 2011;Lunsky et al, 2011;Singh et al, 2011;Snoyman & Aicken, 2011) reported both full-scale IQs and a description of how exactly the level of adaptive functioning had been measured. Only a few provided some/more details on the circumstances of the IQ assessment.…”

Prospective Dynamic Assessment of Risk of Sexual Reoffending in Individuals with an Intellectual Disability and a History of Sexual Offending Behaviour

“…With the paucity of research in the intellectual disability field to date, this study provides important validation of the efficiency of intellectual disability ‐specific tools, with a sample size that is larger than the previous published study (Blacker et al . ). We aimed to improve existing knowledge by (i) including a reasonably large sample of sexual offenders with an intellectual disability, (ii) using a prospective design, (iii) incorporating all ARMIDILO‐S items and (iv) including IQ score information about the sample (the Blacker et al .…”

“…In this study, Blacker et al . () examined the performance of a number of risk assessments including the acute and stable dynamic offender subscale from the ARMIDILO‐S. The risk assessments were coded retrospectively from file information.…”

“…Based on these findings Blacker et al . () suggested that actuarial tools may not be as effective for offenders with an intellectual disability and that measures that incorporate acute and stable dynamic risk factors may result in greater accuracy.…”