Performance Validity and Neuropsychological Outcomes in Litigants and Disability Claimants

Abstract

This study examined the relationship of performance validity and neuropsychological outcomes in a sample of individuals referred for independent neuropsychological examination in the context of reported traumatic brain injury (82% mild). Archival data were examined on 175 participants aged 20 to 65 who were administered at least two performance validity measures. Participants who passed all effort measures (Pass; n = 61) outperformed those who failed two or more (Fail; n = 70) on the majority of tests in the neuropsychological battery. The Fail group showed a higher percentage of impaired test scores than the Pass group with impairment defined at three levels (T scores < 40, 35, and 30). At the most conservative impairment cutoff (T < 30), 16% of the Pass group demonstrated impaired scores on more than three measures, while 79% of the Fail group showed impaired scores on more than three measures. The number of effort measures failed correlated highly with the overall test battery mean (r = −.73). On cognitive domain summary scores, effect sizes based on levels of effort (d = 1.12 to 1.86) were higher than those based on injury severity (d = 0.03 to 0.36).

Keywords:

• Performance validity
• Effort assessment
• Forensic neuropsychology
• Traumatic brain injury

Notes

¹Linear regression models were significant for OTBM, F(1, 59) = 13.89, p < .001, R ² =. 19, FSIQ, F(1, 58) = 16.02, p < .001, R ² =. 22, and language/academic ability, F(1, 59) = 35.46, p < .001, R ² =. 38. Estimated values were calculated using the following formulas: predicted OTBM = 71.73 + (1.56 × Education); predicted FSIQ = 60.24 + (2.76 × Education); and predicted language/academic ability = 58.67 + (2.74 × Education).