Can Overall Adenoma Detection Rate Replace Screening Adenoma Detection Rate ? Multicenter Study

Inclusion Criteria: * consecutive patients aged ≥50 years undergoing colonoscopy are eligible for enrollment. Exclusion Criteria: * high risk family history of colorectal cancer (CRC) e.g., familial adenomatous polyposis, hereditary non-polyposis CRC syndrome, multiple first degree relatives with CRC, or a single first degree relative with CRC at \<60 years * serrated polyposis syndrome * inflammatory bowel disease * colonoscopy to remove a large neoplastic polyps * obstructive lesions of the colon * gastrointestinal bleeding * current participation in other studies * hospitalized patients * mental retardation * pregnancy * refusal to provide a written informed consent.