White Matter Associations With Performance Validity Testing in Veterans With Mild Traumatic Brain Injury: The Utility of Biomarkers in Complicated Assessment.

Only 13 Veterans with mild TBI failed at least one performance validity test, so the key subgroup is small. TBI diagnosis relied largely on retrospective self-report, and the questionnaire used for TBI history was described by the authors as lacking rigorous psychometric evaluation. Poor performance validity was defined as failing either of two tests, and the authors noted stricter criteria might have yielded different findings. The tract-by-tract analyses were exploratory and not corrected for multiple comparisons, so some regional differences may not be reliable. The military controls had no performance validity failures, so the study cannot compare brain findings in controls who fail. Groups differed in education, ethnicity, and time since last injury, which could influence interpretation.

The authors reported no conflicts of interest.

Do not conclude that a failed performance validity test proves no genuine impairment. In this study, Veterans who failed also had worse cognitive test performance and more white matter abnormalities on one scan measure than Veterans who passed.