An analysis of the clinical features of familial schizophrenia

Clinical features of familial schizophrenia were examined in 169 siblings from 80 families. Factor analysis of symptoms produced a negative symptom factor (affective flattening and negative thought disorder), a disorganization factor (inappropriate affect and positive thought disorder) and a reality distortion factor (delusions and hallucinations). The negative symptom factor correlated positively with duration of illness and poor outcome. The disorganization factor correlated positively with poor outcome and early age at onset. The only clear correlation between these factors and affective symptoms was a negative one between the negative symptom factor and mania. There were no significant gender differences in age at onset, factor scores or outcome. The implication of these findings in relation to recent research in the areas of psychopathology and epidemiology are discussed.