AGE-OF-ONSET IN FAMILIAL AND SPORADIC SCHIZOPHRENIA

We have studied the gender and family history differences with regard to age of onset of schizophrenia. These differences have often been vi ewed as an important clue to the aetiology of the illness. Patients fr om three centres in Europe and Canada were included in the study. A sa mple of 1089 subjects was categorized according to the subject's sex, family history of schizophrenia, and the centre. The principal statist ical method was analysis of variance. Patients with no family history of schizophrenia had a consistently higher average age of onset. This effect was seen in both male and female subjects across all three grou ps. These results support the relationship between familial risk and e arly onset, but no interaction of gender and family history was found.