The need for epidemiologist and surgeons to cooperate in the evaluation of surgical therapies.
D002763:Cholecystectomy; D002769:Cholelithiasis / Q000453:epidemiology; D003452:Cryosurgery / Q000009:adverse effects; D004381:Duodenal Ulcer / Q000628:therapy; D004812:Epidemiologic Methods; D005069:Evaluation Studies as Topic; D005705:Gallbladder Diseases / Q000453:epidemiology; D006801:Humans; D010919:Placebos; D013514:Surgical Procedures, Operative / Q000009:adverse effects / Q000592:standards
D010919:Placebos