Examination of performance validity test failure in relation to number of tests administered

This study examined the relationship among performance validity test (PVT) failure, number of PVTs administered, and participant characteristics including demographic, diagnostic, functional, and contextual factors in a clinical sample (N = 158) of outpatient physiatry referrals. The number of PVTs failed and the number administered showed a small non-significant correlation (r_s =.13, p =.10). Participant characteristics showed associations with PVT failure consistent with prior research. A negative binomial regression model was fitted using number of PVTs failed as outcome and age, education, number of PVTs administered, clinical versus medico-legal context, and functional status as predictors. Although education and functional status were significant predictors of number of PVTs failed, the number of PVTs administered was not. A second analytic approach focused on observed false positive rates in a neurologic no-incentive (NNI) sample subset (n = 87). In contrast to a recent proposal based on statistical simulation, observed false positive rates were lower than predicted rates in NNI participants administered six, seven, or eight PVTs using a two-PVT failure cutoff. These results are interpreted as mitigating concerns that increased PVT failure is necessarily the outcome of increased PVT administration.