Cost-effectiveness of risperidone, olanzapine, and conventional antipsychotic medications.

To assess the cost and effectiveness of risperidone, olanzapine, and conventional antipsychotic medications under "usual practice" conditions in a large, public mental health system, 108 persons diagnosed with schizophrenia or schizoaffective disorder were randomly assigned to one of these three medication groups and followed prospectively over a 12-month period using standard instruments and procedures. Psychiatric medication costs increased more over time in both the olanzapine and risperidone groups than in the conventional medication group. Compliance with the prescribed medication was higher in the olanzapine group than in the conventional group. No differential effects by medication group were evident in this sample on the symptoms of schizophrenia, side effects, psychosocial functioning, time to discharge for index hospitalization, survival to initial rehospitalization, or client satisfaction with services. These results extend findings from previous efficacy and naturalistic studies in several ways but are limited chiefly by the small number of subjects who completed 6 to 12 months of the clinical trial, and the resulting power to detect differences in the statistical analyses.