Phase 4 Study to Evaluate Efficacy of Paliperidone Extended-Release(ER) in Schizophrenic Participants

The purpose of this study is to investigate the efficacy of flexibly dosed paliperidone extended-release (mechanism to dissolve a drug over time in order to be released slower and steadier into the blood stream) in improving or maintaining the subjective symptoms of the participants in three participants' groups (that is, by the reason to switch: lack of efficacy group, lack of tolerability group, and lack of compliance group) who switched from other previous antipsychotic drugs to paliperidone extended-release tablets at flexible doses.