A comparative study on schizophrenia diagnosed by ICD-9 and DSM-III: course, family history and stability of diagnosis.

Data from the Taipei Center of the International Pilot Study of Schizophrenia were reanalyzed using the ICD-9 and DSM-III diagnoses at 7-year follow-up. Patients diagnosed as schizophrenic according to DSM-III were shown to be a more homogeneous group in terms of their clinical manifestations, social functions and family psychiatric history than those defined as schizophrenic by ICD-9. The discordant cases of ICD-9 schizophrenia and DSM-III affective disorders were found to be different from the concordant schizophrenic group, but similar to the concordant group of affective disorders diagnosed by ICD-9 and DSM-III. Thirty-five per cent of mood-incongruent psychotic major depressive disorders defined by DSM-III at initial evaluation were diagnosed as schizophrenia at 7-year follow-up.