title: The schizoaffective phenomenon: the state of the art.
abstract: OBJECTIVE
  Schizoaffective disorders are well established. Nevertheless, the definition in the International Classification of Diseases (ICD)-10 and the Diagnostic and Statistical Manual (DSM)-IV are insufficient.
  
  
  METHODS
  Critical review of the literature from Kahlbaum (1863) to the 21st century.
  
  
  RESULTS
  Many authors have described people suddenly developing a disorder with both 'schizophrenic' and 'affective' symptoms. In DSM-IV and ICD-10, the schizoaffective disorder is defined as the concurrent occurrence of schizophrenic symptoms with a major affective disorder. However, there is no reason for a chronological distinction regarding the co-existence of schizophrenic and affective symptomatology. Moreover, longitudinal aspects are not included in the definitions.
  
  
  CONCLUSIONS
  Two types of schizoaffective disorder must be distinguished: the 'concurrent' and the 'sequential' type. The first includes people having only a coincidence of schizophrenic and affective symptoms. The 'sequential' type is defined as the schizoaffective disorder under a longitudinal aspect subsuming disorders with a symptom change between different episodes. Consequences for further research are discussed in detail.
authors.affiliation: Department of Psychiatry and Psychotherapy, Martin-Luther University Halle-Wittenberg, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Marneros
mesh_terms: D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D018450:Disease Progression; D006801:Humans; D008137:Longitudinal Studies; D011618:Psychotic Disorders / Q000145:classification / Q000175:diagnosis / Q000523:psychology*; D009626:Terminology as Topic