<qa>  What is the focus of the Phase IV study?This Phase IV, randomized, parallel-group study is designed to evaluate the cataractogenic potential of quetiapine fumarate SEROQUEL compared with that of a putative non-cataractogenic antipsychotic medication risperidone RISPERDAL. This study is being conducted to fulfill the SEROQUEL Phase IV commitment regarding evaluation of cataractogenic potential. 