A taxometric analysis of schizophrenia symptoms

Psychiatry Res. 2007 Apr 15;150(3):245-53. doi: 10.1016/j.psychres.2006.01.019. Epub 2007 Feb 21.

Abstract

Specific disorders within the psychosis syndrome have been proposed although no definitive validation of subtypes has been achieved. If there are subtypes of psychosis, latent discontinuity between clinical descriptors should be found. We applied for the first time taxometric analysis on characteristic schizophrenia symptoms. The sample consisted of 660 inpatients with an acute psychotic episode. Computed scores of the clinical dimensions included in the three-syndrome model of schizophrenia symptomatology were used as clinical descriptors or latent variables to be analyzed. Two taxometric analyses were used (MAXCOV and MAMBAC). Discrepancies between observed covariance curves and between the estimated base rates of indicators did not support a taxonic conjecture within psychosis based on the severity of 'Psychosis', 'Negative' and 'Disorganization' dimensions scores, which were used as indicators. However, no appropriate solution could be reached because the three clinical indicators of schizophrenia symptomatology used in this study showed a lack of consistency. The lack of a taxonic structure with symptomatological domains of psychosis suggested the existence of a dimensional solution for schizophrenia symptomatology within psychoses.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Affect
  • Diagnostic and Statistical Manual of Mental Disorders
  • Female
  • Humans
  • Male
  • Psychotic Disorders / classification
  • Psychotic Disorders / diagnosis
  • Psychotic Disorders / epidemiology
  • Schizophrenia / classification*
  • Schizophrenia / diagnosis*
  • Schizophrenia / epidemiology
  • Schizophrenic Psychology
  • Severity of Illness Index
  • Surveys and Questionnaires