A Cochrane review included 3 studies with a total of 211 subjects. Analysis was complicated by the heterogeneity in populations (adults and children), the wide range of instruments used to measure outcomes, and the variety in presentation of results. Some evidence of the benefits of risperidone in irritability, repetition and social withdrawal were apparent. Weight gain was the most most prominent adverse effect.
Comment: The quality of evidence is downgraded by sparse data and inconsistency.