Riccioni, M E How can we compare apples and oranges? [electronic resource] - The American journal of gastroenterology Nov 2010 - 2504; author reply 2504-5 p. digital Publication Type: Comment; Letter ISSN: 1572-0241 Standard No.: 10.1038/ajg.2010.283 doi Subjects--Topical Terms: Endoscopes, GastrointestinalEndoscopy, Gastrointestinal--methods