This study was a multicenter, open-labeled, blinded-endpoint, randomized controlled trial evaluating the impact of adding IOT to GOT for patients with schizophrenia. The study took place between February 2016 and March 2017 during an OT program affiliated with Japanese psychiatric hospitals, including one public hospital and five private hospitals in Nagano Prefecture, Japan, which is a suburban community. Treatment in this study lasted approximately 3 months from hospitalization to discharge.