White Light vs Narrow Band Imagingin the Diagnosis of Right Sided Colonic Polyps in Asymptomatic Subjects Undergoing Screening Colonoscopy

Inclusion Criteria: * Asymptomatic subjects undergoing screening colonoscopy * age \> 50. * average risk subjects defined as those without a personal history of inflammatory bowel disease, colon adenoma or cancer or family history of FAP or Familial non-polyposis syndrome or first degree relatives having diagnosed to have colo-rectal carcinoma, no colonoscopy in past 5 years and, ability to provide a written consent to trial participation Exclusion Criteria: * unable to consent