Gender differences on the WAIS-IV in patients with schizophrenia

Abstract

Introduction. Results from studies that have investigated gender differences in neuropsychological functioning in schizophrenia have been inconsistent. Differences in the illness stage, in the demographic and clinical characteristics of the samples, and the instruments used to measure cognition may have contributed to the heterogeneity in the results. Objective. Investigate the heterogeneity in the results comparing cognitive functioning in chronically ill male and female patients with schizophrenia. Method. Twenty-five women and twenty-five men chronically ill patients with schizophrenia matched on age, age at illness onset, and years of education were evaluated in cognitive functioning using the WAIS-IV. Results. Men showed higher scores than women on the two global measures, on the perceptual reasoning and working memory indices, and on the information, visual puzzles, digit span, and arithmetic subtests of the WAIS-IV. Cohen’s d effect sizes were high for the two global measures and the two indices (d > .68). Discussion and conclusion. Overall, in chronically stable patients with diagnosis of schizophrenia, women’s performance on cognitive functioning was below men’s when assessed with the WAIS-IV, except in the case of processing speed. This pattern of gender differences is similar to the pattern observed in healthy populations. Our results can help to clarify the heterogeneity in the results from studies on gender differences in cognitive functioning in schizophrenia and may be valuable in designing cognitive-targeted interventions for schizophrenia.