Comparison between the Test of Memory Malingering (TOMM) and the Nonverbal Medical Symptom Validity Test (NV-MSVT) in adults with disability claims.

In this study, the Nonverbal Medical Symptom Validity Test (NV-MSVT; Green, 2008) and the Test of Memory Malingering (TOMM; Tombaugh, 1996) were given to a consecutive series of outpatients undergoing disability assessment. No cases of moderate to severe traumatic brain injury (TBI) failed the easy NV-MSVT subtests or the TOMM. However, 26% of the mild TBI group failed the NV-MSVT and 10% failed the TOMM. More than 10% of the whole sample passed the TOMM but failed the NV-MSVT. Using profile analysis, the NV-MSVT has been shown to have a zero false-positive rate in three independent groups of patients with severe cognitive impairment arising from dementia. The more severe the actual cognitive impairment, the more likely it is that false positives for poor effort will occur. Therefore, using the same criteria, we would also expect zero false positives in people with much less severe impairment, such as mild TBI. Those in the current study who passed the TOMM and failed the NV-MSVT had profiles that were not characteristic of people with actual severe impairment. Instead, they were of the paradoxical type seen in simulators. The results suggest that the NV-MSVT is considerably more sensitive to poor effort than the TOMM, if the conventional cutoff is used to define TOMM failure.