Comparison between the Brief Psychiatric Rating Scale and the Manchester Scale for the rating of schizophrenic symptoms.

A reliability study was carried out to compare the short Manchester Scale (MS) to the longer Brief Psychiatric Rating Scale (BPRS), to see if similar items scored the same aspect of pathology and to find the sources of error. The raters were a psychiatrist and a psychologist cum medical student; they had recently arrived in Britain, came from different cultures and had not used the scale previously. Comparisons between the scales were made by interviewing the patients separately and together using either one or both scales. The items on the MS showed a higher interrater reliability as compared to the BPRS, both with independent and simultaneous ratings. Items based on observation only correlated poorly as compared to items based on verbal report. Lower between-scale correlations for delusions and affect were observed even where the same rater used the two scales, suggesting that the scales have different meanings for these items. The MS is a suitable alternative to the BPRS for quantifying schizophrenic symptoms.