The factor structure for positive and negative symptoms in South African Xhosa patients with schizophrenia

Most studies investigating the symptom dimensions of schizophrenia utilisin g the Scale for the Assessment of Negative Symptoms (SANS) and the Scale fo r the Assessment of Positive Symptoms (SAPS) favour a three factor model. T his study sought to investigate the factor structure of both the global and individual items of the SANS and SAPS in a large sample of South African X hosa patients with schizophrenia. A total of 422 subjects participated. Bot h principal components and factor analytical procedures were applied. For t he global items, a two-factor solution representing positive and negative s ymptoms accounted for 59.9% of the variance. Alternatively, the three-dimen sional model of negative, psychotic and disorganisation factors was support ed by a five-factor solution if the more heterogeneous items of attention a nd alogia were ignored. Analysis of the individual items yielded a five-fac tor solution with the negative symptoms splitting into diminished expressio n and disordered relating, and the positive symptoms separating into factor s for psychosis, thought disorder and bizarre behaviour. Our findings are v ery similar to those from other parts of the world, providing evidence that the factor structure for the symptoms of schizophrenia is relatively resis tant to cultural influences. This is particularly true for negative symptom s. (C) 2001 Elsevier Science B.V. All rights reserved.