A clinical study to evaluate the efficacy, safety and tolerability of two dose ranges of risperidone (1 to 3 mg/day, and 4 to 6 mg/day) versus placebo (an inactive substance like a sugar pill) in adolescents (aged 13 to 17 years) with schizophrenia (i.e. abnormal behavior and thoughts). The study duration is about 6 to 7 weeks.

Subjects will be aged 13 to 17 years with a diagnosis of schizophrenia. On enrollment, subjects will be assigned to receive 1 of 3 treatments (oral placebo tablets, oral risperidone tablets 1 to 3 mg, or oral risperidone tablets 4 to 6 mg), which will be administered daily for 6 weeks. Study medication will be increased to within the target dosage range during the first 7 days and then further increased until the maximum tolerated dose is achieved by day 14. The maximum tolerated dose will be maintained for the last 4 weeks of the study, unless dose adjustments are agreed with the Sponsor. Risperidone (1 to 3 mg or 4 to 6 mg) or placebo given orally as 0.5, 1, 2, 3, or 4 ,g tablets (or matching placebo) each day for 6 weeks.

Inclusion Criteria:

• A responsible person must be available to accompany the subject to the site at each visit
• patient must meet the DSM-IV criteria for schizophrenia

Exclusion Criteria:

• Patients with mild, moderate or severe mental retardation
• patients with a known or suspected history of substance dependence
• subjects weighing <35kg
• subjects who cannot swallow oral tablets