Patients All consecutive patients who were scheduled for colonoscopy were included. Exclusion criteria were: patients scheduled for partial colonoscopy, interventional colonoscopy (for stent insertion, stenosis dilation).
Data collection The following data have been prospectively collected: age, gender, indication for colonoscopy, preparation procedure and quality of the preparation (assessed by the Boston Bowel Preparation Scale; BBPS) [19-20], caecal intubation (yes/no), withdrawal time, number and size of polyps and polyp histopathology.
All clinical data were collected during the procedure by a nurse and an endoscopist on a dedicated software. The database was then supplemented by the Clinical Research Associate for histopathological data.
We determined adenoma detection rate (ADR; percentage of colonoscopies with at least one adenoma), polyp detection rate (PDR: percentage of colonoscopies with at least one polyp), mean number of polyps per colonoscopy (MNP), large polyp detection rate (LPDR; percentage of colonoscopies with at least one polyp of 1 cm or more) and advanced neoplasia detection rate (ANDR: percentage of colonoscopies with at least one advanced neoplastic lesion as defined below).