Wisconsin Card Sorting Test dimensions in schizophrenia: factorial, predictive, and divergent validity

This study explored the factor structure of the Wisconsin Card Sorting Test (WCST). Scores from 197 participants with schizophrenia or schizoaffective disorder were subjected to an exploratory factor analysis that yielded three factors: Perseveration, Nonperseverative Error, and Inefficient Sorting. Comparison with two previous factor analyses revealed remarkable factorial invariance. Correlations with subject and illness characteristics, symptom dimensions, and work performance demonstrated predictive and divergent validity for the three factors. However, a representative item from each factor yielded similar correlations with very little loss of power suggesting that the factors are composed of highly redundant items. When data reduction is necessary, schizophrenia researchers are justified in using three variables: perseverative error, nonperseverative error, and failure to maintain set, to represent WCST performance.