Factor Structure of the Positive and Negative Syndrome Scale (PANSS) Differs by Sex.

Although the Positive and Negative Syndrome Scale (PANSS) is widely used in clinical research, factor analytic studies of the scale have been inconsistent and questions remain about the underlying factor structure of schizophrenia symptoms. The purpose of this study was to examine whether the factor structure of the PANSS differs in men and women with schizophrenia. Principal components analysis (PCA) with equamax rotation was used to examine the factor structure of the PANSS separately in 124 males and 74 females with schizophrenia-related psychoses. In males, a four-factor structure was identified: 1) Negative, 2) Cognitive, 3) Positive, and 4) Hostility. In females, a four-factor structure also emerged: 1) Negative, 2) Cognitive, 3) Positive, and 4) Depression. The most notable difference between the male and female PCAs was the presence of a depression factor in the females and a hostility factor in males. These results support sex differences in the factor structure of schizophrenia symptoms, which has important implications for clinical research.