Schizophrenic patients have been widely reported to fail in performing Wisconsin Card Sorting Test (WCST). These data have been mostly interpreted as cognitive difficulties and/or neurofunctional impairment inherent to schizophrenia. Nevertheless, checking sample characteristics, the importance of variables as education appears relevant. In our study we examined schizophrenic patients and controls with low and high educational levels respectively. ANOVA results show significant differences on WCST performances for the variable diagnosis (schizophrenics and controls) and for the variable educational level (low and high educational level). It therefore seems necessary call for caution in interpreting WCST results in schizophrenic patients when educational level is not considered.