Response time measures on the Word Memory Test do not add incremental validity to accuracy scores in predicting noncredible neurocognitive dysfunction in mild traumatic brain injury litigants.

The objective of the current study was to investigate whether response time measures on the Word Memory Test (WMT) increase predictive validity on determining noncredible neurocognitive dysfunction in a large sample of mild traumatic brain injury (MTBI) litigants. Participants included 203 adults who underwent a comprehensive neuropsychological examination. Criterion groups were formed based upon their performance on stand-alone measures of cognitive performance validity (PVT). Participants failing PVTs exhibited significantly slower response times and lower accuracy on the WMT compared to participants who passed PVTs. Response time measures did not add significant incremental validity beyond that afforded by WMT accuracy measures alone. The best predictor of PVT status was the WMT Consistency Score (CNS) which was associated with an extremely large effect size ( d  = 16.44), followed by Immediate Recognition (IR: d  = 10.68) and Delayed Recognition (DR: d  = 10.10).