When Failing One Performance Validity Test Matters

There appears to be a lack of consensus regarding how best to interpret cognitive test findings when there is a failure on only one Performance Validity Test (PVT). The current study examined the impact of failing one freestanding, forced-choice, memory-based (Fr-FC-MB) PVT across two memory measures in a large sample of veterans (N = 1,353). The impact of failing zero, one, or two Fr-FC-MB PVTs (Test of Memory Malingering Trial 1 or the Medical Symptom Validity Test) on subsequent memory measures was examined (California Verbal Learning Test-II [CVLT-II], Brief Visuospatial Memory Test-R [BVMT-R]). Compared to those failing zero PVTs, those failing one PVT showed significant declines across all memory indices with large average effect sizes (BVMT-R, d = -0.9, CVLT-II, d = -1.0). Those failing one PVT had memory scores more similar to those failing two PVTs. There is a need for greater nuance and flexibility when determining invalid test performance. The current findings, along with a brief review of the literature, find that failing even one Fr-FC-MB PVT dramatically (negatively) impacts memory performance. Results suggest that including individuals failing one Fr-FC-MB PVT into a credible group should be more closely scrutinized.