The Dot Counting Test adds up: Validation and response pattern analysis in a mixed clinical veteran sample

ABSTRACT

Objective: This study cross-validated the Dot Counting Test (DCT) as a performance validity test (PVT) among a mixed clinical veteran sample. Completion time and error patterns also were examined by validity group and cognitive impairment status.

Method: This cross-sectional study included 77 veterans who completed the DCT during clinical evaluation. Seventy-four percent (N = 57) were classified as valid and 26% as noncredible (N = 20) via the Word Memory Test (WMT) and Test of Memory Malingering (TOMM). Among valid participants, 47% (N = 27) were cognitively impaired, and 53% (N = 30) were unimpaired.

Results: DCT performance was not significantly associated with age, education, or bilingualism. Seventy-five percent of the overall sample committed at least one error across the 12 stimulus cards; however, valid participants had a 27% higher rate of 0 errors, while noncredible participants had a 35% higher rate of ≥4 errors. Overall, noncredible individuals had significantly longer completion times, more errors, and higher E-scores. Conversely, those with cognitive impairment had longer completion times, but comparable errors to their unimpaired counterparts. Finally, DCT E-scores significantly predicted group membership with 83.1% classification accuracy and an area under the curve of .87 for identifying invalid performance. The optimal cut-score of 15 was associated with 70% sensitivity and 88% specificity.

Conclusion: The DCT demonstrated good classification accuracy and sensitivity/specificity for identifying noncredible performance in this mixed clinical veteran sample, suggesting utility as a non-memory-based PVT with this population. Moreover, cognitive impairment significantly contributed to slower completion times, but not reduced accuracy.

KEYWORDS:

• Performance validity
• assessment
• veterans
• psychometrics
• Dot Counting Test
• effort.​

Acknowledgments

The authors have no conflicts of interest to report, and none have any financial interest with the subject matter discussed in the manuscript. The views expressed herein are those of the authors and do not necessarily reflect the views or the official policy of the Department of Veterans Affairs or U.S. Government.

Disclosure statement

No potential conflict of interest was reported by the authors.​