The diagnostic category called simple schizophrenia has disappeared from
official American nosology but has been retained in ICD-9. The diagnosis
has a long history, was one of the traditional schizophrenic subtypes
identified by Bleuler, and was later accepted by Kraepelin. The authors
provide a historical overview of the concept, review its modern successors,
and provide recommendations for its inclusion in DSM- IV as a proposed
diagnostic category needing further study.