Objective Performance validity research has emphasized the need for briefer measures and, more recently, abbreviated versions of established free-standing tests to minimize neuropsychological evaluation costs/time burden. This study examined the accuracy of multiple abbreviated versions of the Dot Counting Test (“quick” DCT) for detecting invalid performance in isolation and in combination with the Test of Memory Malingering Trial 1 (TOMMT1). Method Data from a mixed clinical sample of 107 veterans (80 valid/27 invalid per independent validity measures and structured criteria) were included in this cross-sectional study; 47% of valid participants were cognitively impaired. Sensitivities/specificities of various 6- and 4-card DCT combinations were calculated and compared to the full, 12-card DCT. Combined models with the most accurate 6- and 4-card combinations and TOMMT1 were then examined. Results Receiver operator characteristic curve analyses were significant for all 6- and 4-card DCT combinations with areas under the curve of .868–.897. The best 6-card combination (cards, 1-3-5-8-11-12) had 56% sensitivity/90% specificity (E-score cut-off, ≥14.5), and the best 4-card combination (cards, 3-4-8-11) had 63% sensitivity/94% specificity (cut-off, ≥16.75). The full DCT had 70% sensitivity/90% specificity (cut-off, ≥16.00). Logistic regression revealed 95% classification accuracy when 6-card or 4-card “quick” combinations were combined with TOMMT1, with the DCT combinations and TOMMT1 both emerging as significant predictors. Conclusions Abbreviated DCT versions utilizing 6- and 4-card combinations yielded comparable sensitivity/specificity as the full DCT. When these “quick” DCT combinations were further combined with an abbreviated memory-based performance validity test (i.e., TOMMT1), overall classification accuracy for identifying invalid performance was 95%.

Current standards of practice in neuropsychology advocate for including validity tests (PVTs). Abbreviating PVTs, such as the Test of Memory Malingering (TOMM), may help reduce overall evaluation time while maintaining diagnostic accuracy. TOMM Trial 1 performance (T1), as well as the number of errors within the first 10 items of Trial 1 (TOMMe10), have shown initial promise as abbreviated PVTs but require additional external cross-validation. This study sought to replicate findings from other mixed, diverse, clinical samples and provide further validation of abbreviated administrations of the TOMM. Data included 120 veterans who completed the TOMM and 3 criterion PVTs during clinical evaluation. In total, performance from 68% of the sample was classified as valid (52% met criteria for cognitive impairment), and performance from 32% of the sample was invalid. Group differences, diagnostic accuracy statistics, and receiver operating characteristic (ROC) curves were analyzed for relevant TOMM indices. There were large (ηp2 = .45–.66), significant differences between validity groups (p < .001) on TOMM T1 and TOMMe10, with lower TOMM T1 and higher TOMMe10 scores for participants with invalid performance. Using established cut-scores, sensitivities/specificities were: TOMMe10 ≥1 error: .84/.66; ≥2 errors: .74/.93; TOMM T1 ≤40: .82/.93. ROC curve analysis yielded significant areas under the curve for both TOMMe10 and T1 with respective optimal cut-scores of ≥2 errors (.74 sensitivity/.93 specificity) and ≤41 (.84 sensitivity/.91 specificity). TOMMe10 and T1 performances are minimally impacted by cognitive impairment. Although both evidenced robust psychometric properties, TOMM T1 continued to show greater accuracy than TOMMe10.

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