SA29. Executive Functioning Success: Exploring the Factor Structure of Successful Completion of the Wisconsin Card Sorting Test in Schizophrenia

Abstract

Background: The present study explored the factor structures of the Wisconsin Card Sorting Test (WCST). This was to assess potential underlying infuences that contribute to a failure to meet the 6 categories completed termination criteria in patients with schizophrenia and healthy controls. Method(s): A total of 139 patients with schizophrenia/schizoaffective disorder and 199 heathy controls completed the electronic version of the WCST. Data for this study were collected through an ongoing collaboration between the CRC for Mental Health and the Monash Alfred Psychiatry Research Centre's Cognitive Neuropsychiatry Team. The sample was split into 2 subgroups based on those who met the categories completed termination rule by successfully completing 6 categories before 128 trials had come to pass and those who did not and used all 128 cards. Seven WCST variables were submitted for factor analysis (FA): Total Correct (TC), Perseverative Responses (PR), Perseverative Errors (PE), Nonperseverative Errors (NPE), Percent Conceptual Level Responses (PCLR), Categories Completed (CC), and Failure to Maintain Set (FMS). Result(s): Factor analysis using a principle components method with direct oblimin rotation resulted in differing 3-factor solutions across the 2 sample subgroups. In the failed to meet the category completed subgroup, a general executive function factor (PCLR, TC, and CC), error/perseveration factor (PR, PE, and NPE), and memory factor (FMS) emerged. Post hoc comparisons across the factor revealed that in this cohort, patients demonstrated a more severe degree of impairment on the general executive function factor and the memory factor compared to controls. For those who successfully completed the task within 128 trials, a perseveration factor (PE, PR, NPE, and PCLR), memory factor (FMS and TC) and a consistency factor (CC) emerged. Post hoc comparisons revealed that in this cohort, patients demonstrated greater impairments on all 3 factors. Conclusion(s): These results provide an insight into the differing cognitive profles of schizophrenia patients who exhibit more pronounced executive functioning defcits as operationalized through failing to complete the WCST. Researchers who employ the WCST among schizophrenia samples should be wary of the underlying impairment differences between patients who do and do not meet the categories completed termination rule.