Schizophrenia Subtypes
Schizophrenia Subtypes
The subtypes of Schizophrenia are defined by the predominant symptomatology at the time of evaluation. Although the prognostic and treatment implications of the subtypes are variable, the Paranoid and Disorganized Types tend to be the least and most severe, respectively. The diagnosis of a particular subtype is based on the clinical picture that occasioned the most recent evaluation or admission to clinical care and may therefore change over time. Not infrequently, the presentation may include symptoms that are characteristic of more than one subtype. The choice among subtypes depends on the following algorithm: Catatonic Type is assigned whenever prominent catatonic symptoms are present (regardless of the presence of other symptoms); Disorganized Type is assigned whenever disorganized speech and behavior and flat or inappropriate affect are prominent (unless Catatonic Type is also present); Paranoid Type is assigned whenever there is a preoccupation with delusions or frequent hallucinations are prominent (unless the Catatonic or Disorganized Type is present). Undifferentiated Type is a residual category describing presentations that include prominent active-phase symptoms not meeting criteria for the Catatonic, Disorganized, or Paranoid Type; and Residual Type is for presentations in which there is continuing evidence of the disturbance, but the criteria for the active-phase symptoms are no longer met.
Because of the limited value of the schizophrenia subtypes in clinical and research settings (e.g., prediction of course, treatment response, correlates of illness), alternative subtyping schemes are being actively investigated. The alternative with the most empirical support to date proposes that three dimensions of psychopathology (psychotic, disorganized, and negative) may come together in different ways among individuals with Schizophrenia. This dimensional alternative is described in Appendix B (p. 765).