Brief screening indexes for malingering: A confirmation of vocabulary minus digit span from the WAIS-III and the rarely missed index from the WMS-III

This study investigated the specificity of empirically derived screening measures for the detection of symptom exaggeration in persons with a diagnosis of alcohol abuse (n = 30), polysubstance abuse (n = 43), or head trauma (n = 27). The first measure evaluated was Vocabulary (V) minus Digit Span (DS) (Mittenberg, Theroux-Fichera, Zielinski, & Heilbronner, 1995); the second measure was the Rarely Missed Index (RMI) for the WMS-III Logical Memory subtest (Killgore & Delta-Pietra, 2000). V-DS misclassified 0% of individuals in the alcohol abuse group, 2% of those in the polysubstance abuse group, and 0% of head injury cases. RMI misclassification rates were 3%, 5%, and 7% for the alcohol abuse, polysubstance abuse, and head injury groups, respectively. Overall accuracy rates were 99% for V-DS and 95% for RMI.