What does the PANSS mean?

Schizophr Res. 2005 Nov 15;79(2-3):231-8. doi: 10.1016/j.schres.2005.04.008. Epub 2005 Jun 27.


Objective: Despite the frequent use of the Positive and Negative Syndrome Scale (PANSS) for rating the symptoms of schizophrenia, the clinical meaning of its total score and of the cut-offs that are used to define treatment response (e.g. at least 20% or 50% reduction of the baseline score) are as yet unclear. We therefore compared the PANSS with simultaneous ratings of Clinical Global Impressions (CGI).

Method: PANSS and CGI ratings at baseline (n = 4091), and after one, two, four and six weeks of treatment taken from a pooled database of seven pivotal, multi-center antipsychotic drug trials on olanzapine or amisulpride in patients with exacerbations of schizophrenia were compared using equipercentile linking.

Results: Being considered "mildly ill" according to the CGI approximately corresponded to a PANSS total score of 58, "moderately ill" to a PANSS of 75, "markedly ill" to a PANSS of 95 and severely ill to a PANSS of 116. To be "minimally improved" according to the CGI score was associated with a mean percentage PANSS reduction of 19%, 23%, 26% and 28% at weeks 1, 2, 4 and 6, respectively. The corresponding figures for a CGI rating "much improved" were 40%, 45%, 51% and 53%.

Conclusions: The results provide a better framework for understanding the clinical meaning of the PANSS total score in drug trials of schizophrenia patients with acute exacerbations. Such studies may ideally use at least a 50% reduction from baseline cut-off to define response rather than lower thresholds. In treatment resistant populations, however, even a small improvement can be important, so that a 25% cut-off might be appropriate.

Publication types

  • Clinical Trial
  • Comparative Study
  • Multicenter Study
  • Research Support, N.I.H., Extramural

MeSH terms

  • Adult
  • Antipsychotic Agents / therapeutic use*
  • Databases, Factual
  • Female
  • Humans
  • Male
  • Middle Aged
  • Psychiatric Status Rating Scales*
  • Reference Values
  • Retrospective Studies
  • Schizophrenia / drug therapy*
  • Schizophrenia / physiopathology*
  • Schizophrenic Psychology*
  • Severity of Illness Index
  • Time Factors
  • Treatment Outcome


  • Antipsychotic Agents