When Time is of the Essence: Preliminary Findings for a Quick Administration of the Dot Counting Test

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).

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.

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.

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%.