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While the Neuropsychological Assessment Battery, Screening Module (S-NAB) is a commonly used cognitive screening measure, no composite embedded performance validity test (PVT) formula has yet been described within it. This study sought to empirically derive PVT formulas within the S-NAB using an analog simulation paradigm. Seventy-two university students (M age = 18.92) were randomly assigned to either an Asymptomatic (AS) or simulated mild traumatic brain injury (S-mTBI) group and were administered a neuropsychological test battery that included the S-NAB and standalone and embedded PVTs. The AS group was instructed to perform optimally, and the S-mTBI group received symptom and test coaching to help simulate mTBI-related impairment. Both groups received warnings regarding the presence of PVTs throughout the test battery. Groups showed significant differences (all ps <.001) on all S-NAB domain scores and PVTs. In the S-NAB, the Attention (S-ATT) and Executive Function (S-EXE) domains showed the largest effect sizes (Cohen's ds = 2.02 and 1.79, respectively). Seven raw scores from S-ATT and S-EXE subtests were entered as predictor variables in a direct logistic regression (LR). The model accurately classified 90.3% of cases. Two PVT formulas were described: (1) an exponentiated equation from LR results and (2) an arithmetic formula using four individually meaningful variables. Both formulas demonstrated outstanding discriminability between groups (AUCs =.96–.97) and yielded good classification statistics compared to other PVTs. This study is the first to describe composite, embedded PVT formulas within the S-NAB. Implications, limitations, and appropriate future directions of inquiry are discussed. [ABSTRACT FROM AUTHOR]

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 (rs= .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. [ABSTRACT FROM AUTHOR]