The utility of the structured interview of reported symptoms in a sample of individuals with intellectual disabilities

The challenges of accurate forensic assessment are aggravated when evaluatees have intellectual disabilities. Few studies have addressed the efficacy of forensic assessment in samples diagnosed with an intellectual disability, and those that have typically focus on measures of cognitive effort rather than on feigned psychiatric symptoms. This study focuses on the applicability of the original and revised versions of the Structured Interview of Reported Symptoms (SIRS) in a sample of participants with genuine intellectual disabilities. The SIRS was administered to 43 individuals diagnosed with intellectual disabilities, all of whom were asked to respond honestly. A considerable proportion of these respondents were misclassified as feigning psychiatric symptoms. These misclassifications were most frequent when the respondents had comorbid psychiatric diagnoses. The updated scoring algorithm of the SIRS-2 generated a rate of misclassifications that was substantially lower but that still exceeded published normative data. The implications for forensic assessment are discussed.