title: Relationship between symptomatic improvement and overall illness severity in patients with schizophrenia.
abstract: BACKGROUND
  Whether improvement on ratings of global illness severity is differentially associated with improvement in specific symptom domains in patients with schizophrenia is not well understood. The present study examined the independent relationships between improvement in specific symptom clusters and change in global impressions of illness severity.
  
  
  METHODS
  This study included 589 patients with chronic schizophrenia who were assessed at baseline and after 6 months of antipsychotic treatment. Both clinicians and patients completed the Clinical Global Impressions-Severity of Illness Scale (CGI-S). Symptom severity was assessed using factor scores derived from the Positive and Negative Syndrome Scale.
  
  
  RESULTS
  Change in illness severity ratings made by the clinician and those made by the patient demonstrated moderate overlap. Nearly half of the patients were evaluated as clinically improved during the 6-month period, as rated by the clinician, with less than a third of patients experiencing a reduction in illness severity as determined by both the clinician and themselves. Improvements in clinician-rated CGI-S scores were most strongly associated with reduction in positive symptom severity. In contrast, change in patient-rated CGI-S scores was not linked to reduction in positive symptoms but rather to improvement in depressive and anxiety symptoms. This latter finding remained in a subsample of patients with relatively preserved insight into illness, suggesting that lack of insight cannot account for these findings. Finally, reduction in positive symptoms beyond 2 to 3 points was found to be clinically meaningful.
  
  
  CONCLUSIONS
  In conclusion, change in overall illness severity, as determined by clinicians, is not necessarily interchangeable with patients' view of improvement of their own clinical status. Moreover, changes in the 2 evaluations of illness severity are associated with changes in different symptom domains.
authors: From the *Schizophrenia Division, Centre for Addiction and Mental Health; and †Institute of Medical Science, and ‡Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada.
authors: Gagan
authors: G
authors: Fervaha
authors: Ofer
authors: O
authors: Agid
authors: Hiroyoshi
authors: H
authors: Takeuchi
authors: Jimmy
authors: J
authors: Lee
authors: George
authors: G
authors: Foussias
authors: Gary
authors: G
authors: Remington
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010361:Patients; D011237:Predictive Value of Tests; D011379:Prognosis; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000188:drug therapy*; D012565:Schizophrenic Psychology; D012720:Severity of Illness Index
chemical_list: D014150:Antipsychotic Agents