Are self-report measures of adaptive functioning appropriate for those high in psychopathic traits?

There is ongoing debate about the methods that evaluators should use to assess the adaptive functioning of an individual in an Atkins claim, including the appropriateness of using self-report measures and extent to which adaptive functioning measures are valid for persons with a history of violent offending. This study examined whether offenders' self-report adaptive functioning scores tended to decrease as their level of psychopathic traits increased. Eighty-five male felony probationers completed the self-report version of the Adaptive Behavior Assessment System - II (ABAS-II: Harrison & Oakland, 2003), the Psychopathic Personality Inventory - Revised (PPI-R: Lilienfeld & Widows, 2005), and a brief intelligence screening measure. ABAS-II composite scores were negatively correlated with PPI-R Self-Centered Impulsivity and Coldheartedness scores, but positively correlated with Fearless Dominance scores. These relationships appeared to be due, in part, to over-reporting symptoms of impairment across measures, suggesting that scores on self-report adaptive functioning measures may be especially susceptible to feigning.