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Objective: The addition of Sequencing to WAIS-IV Digit Span (DS) brought about new Reliable Digit Span (RDS) indices and an Age-Corrected Scaled Score that includes Sequencing trials. Reports have indicated that these new performance validity tests (PVTs) are superior to the traditional RDS; however, comparisons in the context of known neurocognitive impairment are sparse. This study compared DS-derived PVT classification accuracies in a design that included adults with verified TBI. Methods: Participants included 64 adults with moderate-to-severe TBI (TBI), 51 healthy adults coached to simulate TBI (SIM), and 78 healthy comparisons (HC). Participants completed the WAIS-IV DS subtest in the context of a larger test battery. Results: Kruskal–Wallis tests indicated that all DS indices differed significantly across groups. Post hoc contrasts revealed that only RDS Forward and the traditional RDS differed significantly between SIM and TBI. ROC analyses indicated that RDS variables were comparable predictors of SIM vs. HC; however, the traditional RDS showed the highest sensitivity when approximating 90% specificity for SIM vs. TBI. A greater percentage of TBI scored RDS Sequencing < 1 compared to SIM and HC. Conclusion: In the context of moderate-to-severe TBI, the DS-derived PVTs showed comparable discriminability. However, the Greiffenstein et al. traditional RDS demonstrated the best classification accuracy with respect to specificity/sensitivity balance. This relative superiority may reflect that individuals with verified TBI are more likely to perseverate on prior instructions during DS Sequencing. Findings highlight the importance of including individuals with verified TBI when evaluating and developing PVTs. [ABSTRACT FROM AUTHOR]

Objective: Embedded validity measures are useful in neuropsychological evaluations but should be updated with new test versions and validated across various samples. This study evaluated Wechsler Adult Intelligence Scale, 4th edition (WAIS-IV) Digit Span validity indicators in post-deployment veterans. Method: Neurologically-intact veterans completed structured diagnostic interviews, the WAIS-IV, the Medical Symptom Validity Test (MSVT), and the b Test as part of a larger study. The Noncredible group included individuals who failed either the MSVT or the b Test. Of the total sample (N = 275), 21.09% failed the MSVT and/or b Test. Diagnostic accuracy was calculated predicting group status across cutoff scores on two Digit Span variables, four Reliable Digit Span (RDS) variables, and two Vocabulary minus Digit Span variables. Results: Digit Span age-corrected scaled score (ACSS) had the highest AUC (.648) of all measures assessed; however, sensitivity at the best cutoff of <7 was only 0.17. Of RDS measures, the Working Memory RDS resulted in the highest AUC (.629), but Enhanced RDS and Alternate RDS produced the highest sensitivities (0.22). Overall, cutoff scores were consistent with other studies, but sensitivities were lower. Vocabulary minus Digit Span measures were not significant. Conclusions: Digit Span ACSS was the strongest predictor of noncredible performance, and outperformed traditional RDS variants. Sensitivity across all validity indicators was low in this research sample, though cutoff scores were congruent with previous research. Although embedded Digit Span validity indicators may be useful, they are not sufficient to replace standalone performance validity tests. [ABSTRACT FROM AUTHOR]