RT Journal Article SR Electronic T1 Reply JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 887 OP 887 DO 10.1136/gut.30.6.887 VO 30 IS 6 A1 Michael Atkinson A1 C S Robertson YR 1989 UL http://gut.bmj.com/content/30/6/887.1.abstract AB