Premorbid Measures and Sports-Related Mild Traumatic Brain Injury: Appropriateness and Accuracy

Open Access
Bailey, Christopher M.
Graduate Program:
Doctor of Philosophy
Document Type:
Date of Defense:
July 10, 2006
Committee Members:
  • Peter Andrew Arnett, Committee Chair
  • Frank Gerard Hillary, Committee Member
  • William Ray, Committee Member
  • Clancy B Blair, Committee Member
  • Wechsler Test of Adult Reading
  • Athlete
  • Baseline
  • Concussion
  • MTBI
The current study examined the accuracy of estimating baseline neuropsychological performance using a variety of methods (Wechsler Test of Adult Reading, WTAR; demographically-based methods; and empirically constructed methods). 103 collegiate athletes were administered baseline mild traumatic brain injury (MTBI) neuropsychological batteries. 19 of these participants sustained concussions and were used in post-MTBI analyses. Initial baseline estimates were developed according to demographics [WTAR demographics-only and Barona et al. (1984) methods], WTAR reading performance (WTAR-P), and WTAR performance plus demographics (WTAR-PD). Correlations between each estimated baseline and observed baseline measure were conducted. Also, separate repeated measures ANOVAs were conducted comparing observed baseline performance and each estimation method with significant demographic groups entered as between-subject factors. Stepwise regressions predicting the observed baseline performance were also conducted by entering the above estimation methods and significant demographic variables (age, sex, race, previous concussion status, and sport). The proportions of accurately estimated baselines were also compared using Binomial Tests for each measure. Difference scores between observed and estimated baseline standard scores and post-injury standard scores were created and compared for the post-MTBI sample with repeated measure ANOVAs. The proportions of declined participants when utilizing observed or estimated baselines were compared using Binomial Tests for each measure. Mild to moderate effects were observed on correlations and few mean differences were observed on the baseline repeated measure ANOVAs. Stepwise regressions showed a pattern of selecting demographic factors (especially race) and demonstrated generally moderate effects. Few accuracy differences were observed on the Binomial Tests, though some measures demonstrated differential accuracy for demographic-based or word-reading-based estimates. No decrement in sensitivity to the cognitive change associated with MTBI was observed in the post-MTBI analyses. Increased sensitivity over observed baseline performance was noted for some estimated baselines on some post-MTBI measures. Baselines were estimated moderately well by the estimation methods. The stepwise regressions (which were largely based on race and other demographics) likely provided the best overall estimate for most measures with the WTAR-P providing the best baseline estimate for the DST and Stroop. Neuropsychologists should consider using multiple estimates for baseline performance in clinical situations.