title: Results are better when patients control their own analgesia.
mesh_terms: D000700:Analgesics / Q000008:administration & dosage*; D002986:Clinical Trials as Topic; D006801:Humans; D010149:Postoperative Pain / Q000188:drug therapy*; D011897:Random Allocation; D012646:Self Administration / Q000295:instrumentation / Q000523:psychology
chemical_list: D000700:Analgesics