Reliability and validity of the functional assessment rating scale.

The Functional Assessment Rating Scale was developed as a measure of psychiatric symptomatology and psychosocial impairments. This study was designed to report estimates of reliability and validity with a population of schizophrenic patients. The scale showed very good interrater agreement, test-retest reliability, construct validity, and concurrent validity, so the scale seems a useful measure of psychopathology which may be used to assess and monitor patients displaying severe mental illnesses.