Elevations on select Conners' CPT-II scales indicate noncredible responding in adults with traumatic brain injury.

Elevations on certain Conners' CPT-II scales are known to be associated with invalid responding. However, scales and cutoffs vary across studies. In addition, the methodology behind developing performance validity tests (PVTs) has been challenged for mistaking true impairment for noncredible presentation. Using ability-based tests as a PVT makes clinicians especially vulnerable to this criticism. The present study examined the ability of CPT-II to dissociate effort from impairment in 47 adults clinically referred for neuropsychological assessment. CPT-II scales previously identified as PVTs (Omissions, Commissions, Hit Reaction Time SE, Variability, and Perseverations) produced classification accuracies hovering around .50 sensitivity at .90 specificity. The subsample that failed these PVTs performed within normal range on other tests of working memory, processing speed, visual attention, and executive function. Results suggest that the select CPT-II based PVTs are sensitive to invalid responding, and are associated with depression and anxiety, but are unrelated to cognitive functioning.

The power of timing: Adding a time-to-completion cutoff to the Word Choice Test and Recognition Memory Test improves classification accuracy.

INTRODUCTION: The Recognition Memory Test (RMT) and Word Choice Test (WCT) are structurally similar, but psychometrically different. Previous research demonstrated that adding a time-to-completion cutoff improved the classification accuracy of the RMT. However, the contribution of WCT time-cutoffs to improve the detection of invalid responding has not been investigated. The present study was designed to evaluate the classification accuracy of time-to-completion on the WCT compared to the accuracy score and the RMT. METHOD: Both tests were administered to 202 adults (Mage = 45.3 years, SD = 16.8; 54.5% female) clinically referred for neuropsychological assessment in counterbalanced order as part of a larger battery of cognitive tests. RESULTS: Participants obtained lower and more variable scores on the RMT (M = 44.1, SD = 7.6) than on the WCT (M = 46.9, SD = 5.7). Similarly, they took longer to complete the recognition trial on the RMT (M = 157.2 s,SD = 71.8) than the WCT (M = 137.2 s, SD = 75.7). The optimal cutoff on the RMT (≤43) produced .60 sensitivity at .87 specificity. The optimal cutoff on the WCT (≤47) produced .57 sensitivity at .87 specificity. Time-cutoffs produced comparable classification accuracies for both RMT (≥192 s; .48 sensitivity at .88 specificity) and WCT (≥171 s; .49 sensitivity at .91 specificity). They also identified an additional 6-10% of the invalid profiles missed by accuracy score cutoffs, while maintaining good specificity (.93-.95). Functional equivalence was reached at accuracy scores ≤43 (RMT) and ≤47 (WCT) or time-to-completion ≥192 s (RMT) and ≥171 s (WCT). CONCLUSIONS: Time-to-completion cutoffs are valuable additions to both tests. They can function as independent validity indicators or enhance the sensitivity of accuracy scores without requiring additional measures or extending standard administration time.