title: Crossover trials.
authors: Bing H
authors: BH
authors: Tang
mesh_terms: D002548:Cerebral Revascularization; D006801:Humans; D002532:Intracranial Aneurysm / Q000601:surgery*; D002538:Intracranial Arteriovenous Malformations / Q000601:surgery; D016032:Randomized Controlled Trials as Topic; D012107:Research Design