(a) Study design. (b) Patient flow diagram. ER, early responder; ENR, early non-responder; ENR–OLZ, early non-responder switched to olanzapine; ENR–RIS, early non-responder maintained on risperidone; mg, milligram; SPI, Study Period I; SPII, Study Period II; SPIII, Study Period III; V, Visit; wk, week.