Word Memory Test Predicts Recovery in Claimants With Work-Related Head Injury

Abstract

ObjectiveTo investigate the predictive validity of the Word Memory Test (WMT), a verbal memory neuropsychological test developed as a performance validity measure to assess memory, effort, and performance consistency. DesignCohort study with 1-year follow-up. SettingWorkers' compensation rehabilitation facility. ParticipantsParticipants included workers' compensation claimants with work-related head injury (N=188; mean age, 44y; 161 men [85.6%]). InterventionsNot applicable. Main Outcome MeasuresOutcome measures for determining predictive validity included days to suspension of wage replacement benefits during the 1-year follow-up and work status at discharge in claimants undergoing rehabilitation. Analysis included multivariable Cox and logistic regression. ResultsBetter WMT performance was significantly but weakly correlated with younger age (r=−.30), documented brain abnormality (r=.28), and loss of consciousness at the time of injury (r=.25). Claimants with documented brain abnormalities on diagnostic imaging scans performed better (∼9%) on the WMT than those without brain abnormalities. The WMT predicted days receiving benefits (adjusted hazard ratio, 1.13; 95% confidence interval, 1.04–1.24) and work status outcome at program discharge (adjusted odds ratio, 1.62; 95% confidence interval, 1.13–2.34). ConclusionsOur results provide evidence for the predictive validity of the WMT in workers' compensation claimants. Younger claimants and those with more severe brain injuries performed better on the WMT. It may be that financial incentives or other factors related to the compensation claim affected the performance.