• Schizophrenia subtypes are defined predominantly by manifest symptoms and behavior. This report, based on sign and symptom data from the International Pilot Study of Schizophrenia, addresses three questions: (1) Are traditional subtype diagnoses applied similarly across cultures? (2) Are the various traditional subtypes symptomatically distinguishable from one another? (3) Can cluster analytic techniques define a more distinctive set of schizophrenic subgroups?
Present State Examination data were reduced to 27 psychopathologic signs and symptoms. Profile analysis of variance results indicate that each subtype appears similar, regardless of center of origin. However, this is based on a lack of distinguishing features between different subtypes. On the other hand, when a cluster analytic technique was used, it showed one large and three small subgroups, each readily distinguishable from the others. These subgroups, labeled "usual," "flagrant," "insightful," and "hypochondriacal," are described clinically. If replicated or validated, such subgroups may prove meaningful in future considerations of subdivisions of the schizophrenia syndrome.