B-184: Stroop-Based Embedded Indicators of Performance Validity in Veterans

Abstract

Objective: This study evaluated the Stroop Color-Word Test (SCWT) as an embedded measure of performance validity. Prior studies support several SCWT indicators for detecting invalid test performance in clinical samples. We expanded on prior work by assessing the classification accuracy of established indices in a veteran sample. Method/Data Selection: Participants were selected from a clinical database if they completed SCWT and three criterion performance validity tests (PVTs): Test of Memory Malingering, Word Choice Test, and Wechsler Adult Intelligence Scale–Fourth Edition Digit Span. Participants were categorized invalid if they failed two or more PVTs and valid if they passed all three. Of the initial sample, 98 bilingual veterans were excluded due to a disproportionate rate of PVT failure. The final sample included 279 monolingual veterans (87.8% valid; Mage=57.17, SD=13.32; Meducation=13.96, SD=2.63). Receiver operating characteristic (ROC) analysis examined classification accuracy and optimal cutoffs for SCWT raw and residual scores. Results/Data Synthesis: Groups were comparable for age and diagnosis; the invalid group had lower education (M=13.24, SD=2.65) than the valid group (M=14.07, SD=2.61), t(42.38)=1.71, p=.09. ROC indicated moderate to excellent classification accuracy: Word AUC=0.853 (p<.001), Color AUC=0.856 (p<.001), Color-Word AUC=0.796 (p<.001), Word-residual (AUC=0.84, p<.001), Color-residual (AUC=0.85, p<.001), and Color-Word-residual (AUC=0.78, p<.001). Optimal cutoffs were: Word-raw ≤56 (sensitivity=0.59, specificity=0.90), Color-raw ≤41 (sensitivity=0.62, specificity=0.91), Color-Word-raw ≤18 (sensitivity=0.44, specificity=0.92); Word-residual ≤−44 (sensitivity=0.65, specificity=0.90), Color-residual ≤−32 (sensitivity=0.53, specificity=0.90), Color-Word-residual ≤−18 (sensitivity=0.47, specificity=0.90). Conclusions: Findings support SCWT-based indicators as embedded PVTs in neuropsychological assessment of veterans in outpatient clinical settings. Replication applying the SCWT normative update and further examination among bilingual veterans is recommended.