A total of 400 consecutive patients undergoing unsedated colonoscopy as a part of a national colorectal cancer screening program will be randomly assigned to innovative or conventional examination. Randomization will be based on computer-generated randomization lists. All patients will be blinded so they will not know which techniques will be used to assess lesions found in colon. In innovative colonoscopy group narrow band imaging (NBI) and Dual Focus (DF) function will be used to identify and classify all lesions according. to Kudo and NICE classification. Endoscopic biopsy samples will be taken from all lesions and in vivo endoscopic diagnosis will be compared with final histopathological result. Thus, sensitivity, specificity, diagnostic accuracy, predictive values, likelihood ratio and Youden index will be calculated. As secondary endpoints total examination time, cecal intubation rate and pain intensity (VAS) will be determined. This study will help to establish whether advanced imaging technologies used during colonoscopy may improve diagnostic possibilities and whether they prolong examination time or lead to increase of pain intensity afterwards.