Detection of malingering using atypical performance patterns on standard neuropsychological tests

Cut-off scores defining clinically atypical patterns of performance were identified for five standard neuropsychological and psychological tests: Benton Visual Form Discrimination (VFD), Fingertapping (FT), WAIS-R Reliable Digit Span (RDS), Wisconsin Card Sorting Failure-to-Maintain Set (FMS), and the Lees-Haley Fake Bad Scale (FBS) from the MMPI-2. All possible pair-wise combinations of scores beyond cut-off (e.g., for VFD and FT; for RDS and FBS), correctly identified 21 of 24 subjects (87.5%) meeting criteria for definite malingered neurocognitive dysfunction, and 24 of 27 (88.9%) subjects with moderate to severe closed head injury. On cross-validation, 15 of 17 subjects (88.2%) meeting criteria for probable malingered neurocognitive dysfunction were correctly identified, with 13 of 13 nonlitigating neurologic patients, and 14 of 14 nonlitigating psychiatric patients correctly classified as having motivationally-preserved performance. Combining the derivation and cross-validation samples yielded a sensitivity of 87.8%, specificity of 94.4%, and combined hit rate of 91.6%.