Effort Testing in Schizophrenia and Schizoaffective Disorder: Validity Indicator Profile and Test of Memory Malingering Performance Characteristics

While the Validity Indicator Profile (VIP) and the Test of Memory Malingering (TOMM) are designed to limit the influence of actual cognitive impairment on successful performance, the extent to which cognitive dysfunction does play a role in the assessment of effort should be verified in distinct clinical groups. To date, little research has been conducted on VIP performance in individuals diagnosed with a psychotic disorder. Fifty-four patients with either schizophrenia or schizoaffective disorder were administered the VIP, TOMM, Short Test of Mental Status, and the Wide Range Achievement Test-4 Reading subtest. Specificity rates were compared between tests, with normative data, and with published specificity rates in psychiatric samples. Results indicate that the use of the VIP with psychotic-disordered individuals will generate increased invalid performance profiles, whereas the TOMM is more resilient in this population. Significantly, mental status and estimated intellectual ability were predictive of classifications on the VIP Verbal subtest and the TOMM.