A Brief Symptom Validity Testing Procedure for Logical Memory of the Wechsler Memory Scale-Revised Which Can Demonstrate Verbal Memory in the Face of Claimed Disability

Abstract

The Wechsler Memory Scale-Revised (WMS-R) has no validity index even though commonly used in forensic settings. Recent strategies have been developed to assess validity of a subject's performance. Although helpful in identifying invalid results, these strategies do not actually demonstrate memory ability. The statistical properties of Symptom Validity Testing (SVT) allow for the conclusion that a functional ability in fact exists when a subject suppresses their score below random range. To address this issue, the author developed a forced-choice, two alternative, recognition test for the Logical Memory subtests of the WMS-R incorporating the SVT paradigm. In order to ascertain random properties of the procedure, it was administered to a sample of 155 undergraduates who never heard the Logical Memory stories. Results suggest the procedure is a useful SVT to detect below chance levels of performance in association with the WMS-R. Two case examples of suppressed ability are given. Although not particularly sensitive by definition, the procedure appears to be an efficacious tool that can actually demonstrate recognition ability for individuals claiming no such ability. A five domain conceptualization to assist in diagnosis of malingering is presented.

Key Words:

• Symptom validity testing
• malingering
• memory
• Wechsler Memory Scale