Factor analysis of symptoms in schizophrenia: differences between White and Caribbean patients in Camberwell

Background. The incidence of schizophrenia among African-Caribbeans living in Britain has been frequently reported to be increased. We sought to determine whether the symptom profile in schizophrenic patients from this group differed from that of their White counterparts. Methods. Factor analysis was applied to symptom data obtained by the Present State Examination (PSE) from a group of White (N = 96) and Afro-Caribbean (N = 64) patients who satisfied Research Diagnostic Criteria criteria for broad schizophrenia. We identified six symptom dimensions: mania, depression, first-rank delusions, other delusions, hallucinations and one which comprised both manic and catatonic symptoms. Results. The only difference between the two ethnic groups was seen on the mixed mania-catatonia dimension with the Afro-Caribbean group being over-represented. There were no other significant differences between the groups. Discriminant analysis, however, revealed no significant differences between the groups in any dimension. Conclusions. These results indicate that there are no differences between White and African-Caribbean patients with schizophrenia in terms of the core symptoms of the disorder, however, the African-Caribbean patients may present with more symptoms of a mixed affective nature.