Clinical implications of Brief Psychiatric Rating Scale scores.

BACKGROUND Despite the widespread use of the Brief Psychiatric Rating Scale (BPRS), the clinical meaning of its total score and cut-off values used to define treatment response are unclear. AIMS To link the BPRS to Clinical Global Impression (CGI) ratings. METHOD Equipercentile linking of BPRS and CGI ratings from seven drug trials in acutely ill patients with schizophrenia (n=1979). RESULTS 'Mildly ill' according to the CGI approximately corresponded to a BPRS total score of 31, 'moderately ill'to a BPRS score of 41 and'markedly ill'to a BPRS score of 53.'Minimally improved'according to the CGI score was associated with percentage BPRS reductions of 24, 27 and 30% at weeks 1, 2 and 4, respectively. The corresponding numbers for a CGI rating of 'much improved' were 44, 53 and 58%. CONCLUSIONS The results provide a clearer understanding of how to interpret BPRS total and percentage reduction scores in clinical trials with patients acutely ill with schizophrenia who are experiencing positive symptoms.