Agreement in psychiatric assessment.

In 103 schizophrenic patients we investigated the extent of practice needed in the use of the Brief Psychiatric Rating Scale (BPRS) to enable its reliability to be assessed. The agreement level of the 7 raters was analysed. Generally, the lowest mean agreement found was for the negative symptoms of the BPRS schizophrenia subscale. A high degree of agreement was attained both for the positive symptoms of the BPRS schizophrenia subscale and for the symptoms of the depression--and of the mania subscale. The degree of disagreement observed was due to both individual differences in assessment ability and the rating procedure. These results indicate that it is necessary to state the degree of agreement achieved in studies in which several raters are taking part.