Abstract:
In 2002, the Supreme Court of the United States (SCOTUS) ruled that offenders diagnosed with intellectual disability (ID) could not be sentenced to death (Atkins v. Virginia). Though the judicial determination is made in accordance with the clinical definition, the decision is a legal one. The clinical definition is comprised of three parts: (1) deficits in intellectual functioning; (2) deficits in adaptive functioning; and (3) onset of these deficits during the developmental period, or prior to age 18. Both the assessment of intellectual and adaptive functioning are measured via standardized assessment instruments, and in the case of adaptive behavior, collateral information. As is true for all assessments, the use of standardized measures is important, but only if the product is valid. The aim of this study was to assess the susceptibility of three commonly used measures of adaptive behavior (i.e., SIB-R, ABAS-3, and Vineland-3) to malingering. The study is a replication and extension of a previous study conducted a decade ago by Doane and Salekin (2009). As was found in the original study, the SIB-R was particularly sensitive to detecting biased responding, while the ABAS-3 was the most susceptible to feigned deficits. The Vineland-3, which was not examined in the previous study, demonstrated moderate sensitivity to differentiating between high and low deficit endorsement. Lastly, the influence of knowledge regarding characteristics associated with ID did not aid participants in malingering in a more effective manner; this was true across conditions (i.e., mild, moderate and unspecified ID).
