title: Sounding board. Are randomized trials appropriate for evaluating new operations?
mesh_terms: D001026:Coronary Artery Bypass / Q000401:mortality / Q000592:standards; D004341:Drug Evaluation; D005069:Evaluation Studies as Topic; D006350:Heart Valve Prosthesis / Q000592:standards; D006801:Humans; D011446:Prospective Studies; D011897:Random Allocation; D012107:Research Design; D013514:Surgical Procedures, Operative; D014481:United States