Wisconsin Card Sorting Test Performance after Putaminal Hemorrhagic Stroke

Abstract

The purpose of this study was to compare the performance differences in the Wisconsin Card Sorting Test (WCST) between 55 patients with putaminal hemorrhage (PH) 3 months after stroke and 69 age-matched normal controls. Impairment on WCST was defined as performance greater than 1.64 standard deviation below the control mean. A multivariate analysis of covariance (MANCOVA) controlling for education yielded a significant main effect for group but not for education and interaction of group x education. Univariate analyses revealed significant between-group differences in five WCST measures, including perseverative errors (PE), perseverative responses (PR), conceptual-level responses (CLR), number of categories completed (NCC), and trials to complete the first category (TCC). For patients with PH, z-scores for two WCST indices were within the impaired range: TCC and PR. A high percentage of patients (40-47%) scored in the designated impaired range on NCC, PR, PE, and TCC. The WCST variables discriminated patients from controls with an overall accurate classification rate of 91.9%. Of these, the variables that contributed most to the differentiation between patients and normal controls were PE, CLR, and total number correct (TNC) (a standardized canonical discriminant function coefficient > 0.40). Finally, no significant hemispheric laterality effects emerged on any of the WCST variables. The results of this study provide further evidence of impaired mental set shifting in stroke patients with PH. The implications for rehabilitation professionals are discussed, and recommendations for further research are made.