MALINGERING: THE USE OF A PSYCHOLOGICAL TEST BATTERY TO DETECT TWO KINDS OF SIMULATION (FAKING, BENDER-GESTALT, DISSIMULATION, MMPI).

Abstract

Malingering refers to the voluntary production of false or greatly exaggerated symptoms in pursuit of an obviously recognizable goal. Numerous studies have shown the psychological tests can detect persons faking various mental disorders; however, the majority of these are plagued by methodological flaws that seriously limit their validity and generalizability. The present study employed a contrasted-groups design that allowed for a rigorous test of the hypothesis that a battery of psychological tests can detect persons given a financial incentive to fake insanity or mental retardation. In addition to using two tests previously employed in simulation research (MMPI and Bender Gestalt), an instrument whose sole purpose is to differentiate malingerers from genuinely impaired adults was developed for validation in this study. This pen-and-paper test (the Malingering Scale) consists of 90 arithmetic, vocabulary, information and abstraction items, and requires 20 minutes to complete. One hundred male adults were divided into five groups of 20 subjects. Two groups consisted of genuinely impaired subjects (either mentally retarded or psychotic inpatients). The other three groups were drawn from a population of prison inmates. Two of the latter groups were offered a financial incentive for successful simulation of a mental disorder (either mental retardation or "insanity") while the fifth group consisted of inmates controls (answering honestly). The test battery was administered to all subjects and scored by examiners who were naive to the purpose of the study. A series of item analyses established the internal consistency of the Malingering Scale and identified those items which best differentiate malingerers from the genuinely impaired. These items were assembled into scoring keys for subjects faking each condition. All test scores were then entered into a series of discriminant function analyses which confirmed the hypothesis that the battery provided more powerful discrimination of subject groups than any single test. Overall, 84% of the subjects were accurately classified into their respective group, and 96% of subjects were correctly identified as either malingering or not malingering. The most powerful single instrument proved to be the Malingering Scale. Direction for future research, including the necessity for cross validation of the Malingering Scale, were discussed.