The Utility of the Structured Interview of Reported Symptoms in a Sample of Individuals With Intellectual Disabilities

Abstract

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.

The role of intelligence on performance on the Inventory of Legal Knowledge (ILK)

“…Although previous research has reported that individuals with an intellectual disability who are not suspected of malingering often score in the malingering range on malingering tests (Hayes et al, 1997;Hurley & Deal, 2006;Weiss et al, 2011), no research has examined the role of intelligence on performance on the ILK. Additionally, the majority of the research studying malingering and intelligence has focused solely on intellectual disabilities and not across the full range of IQ scores.…”

“…Many research participants with intellectual deficits score in the feigning range on malingering tests, even when instructed to perform optimally (Dean, Victor, Boone, & Arnold, 2008;Hayes et al, 1997;Hurley & Deal, 2006;Marshall & Happe, 2007;Weiss et al, 2011). Unfortunately, most of the studies examining malingering and intelligence use participants with an intellectual disability instead of those with a range of intellectual deficits.…”

“…The relationship between intelligence and performance on malingering screening measures has been the subject of very few empirical studies and the majority of the studies published on this topic have focused primarily on intellectual disability and malingering and not on a range of intelligence (Hayes, Hale, & Gouvier, 1997;Hurley & Deal, 2006;Weiss, Rosenfeld, & Farkas, 2011). Malingering is the purposeful production of exaggerated or feigned symptoms of a mental or physical disorder which is motivated by external incentives (American Psychiatric Association, 2013).…”

“…Unfortunately, most of the studies examining malingering and intelligence use participants with an intellectual disability instead of those with a range of intellectual deficits. Weiss et al (2011) administered the Structured Interview of Reported Symptoms (SIRS) and SIRS-2 to a sample of 43 individuals with genuine intellectual disabilities. Results from this study indicated that over 40% of the sample was misclassified as likely feigning using the total score on the SIRS and 7% of the sample was misclassified using the total score on the SIRS-2 (Weiss et al, 2011).…”

“…Weiss et al (2011) administered the Structured Interview of Reported Symptoms (SIRS) and SIRS-2 to a sample of 43 individuals with genuine intellectual disabilities. Results from this study indicated that over 40% of the sample was misclassified as likely feigning using the total score on the SIRS and 7% of the sample was misclassified using the total score on the SIRS-2 (Weiss et al, 2011). Hayes et al (1997) administered three malingering tests to individuals who had a diagnosis of an intellectual disability and were not identified as malingering and those who had a diagnosis of an intellectual disability and had previously been identified as malingering.…”