RT Journal Article SR Electronic T1 Number of significant polyps detected per six-minute withdrawal time at colonoscopy (SP6): a new measure of colonoscopy efficiency and quality JF Frontline Gastroenterology JO Frontline Gastroenterol FD BMJ Publishing Group Ltd SP 491 OP 493 DO 10.1136/flgastro-2019-101184 VO 11 IS 6 A1 Rajaratnam Rameshshanker A1 Brian P Saunders YR 2020 UL http://fg.bmj.com/content/11/6/491.abstract AB