565 Background: The aim of EDIFICE surveys is to improve insight into the behavior of the French population with regard to cancer prevention and participation in screening programs. Via the colorectal cancer (CRC) screening program, all average-risk individuals in the 50-74-yr age group are invited every 2 years to do a guaiac-based or immunochemical fecal occult blood test. This analysis focuses on lay-population reasons for not undergoing the test. Methods: The 5th nationwide observational survey was conducted by phone interviews using the quota method. A representative sample of 1299 individuals with no history of cancer (age, 50-74 yrs) was interviewed between 22 November and 7 December 2016. Those who had never undertaken a screening test were asked for their reasons. Results: In total, 64% reported having undergone a screening test (colonoscopy, fecal occult blood test) at least once in their lifetime (coverage). There was a non-significant (NS) increase in coverage rates over the period 2014-2016. In 2016, the most frequently (36%) cited reason for not being screened was “individual negligence/not a priority”. This figure was significantly higher than in 2014 (24%, P < 0.05). Between one in four and one in five respondents answered “no risk factor” in both 2014 and 2016. Approximately one in ten respondents gave “pointlessness” as their reason for not being screened (12% in 2016 vs 8% in 2014, NS) while “fear of the examination or fear of the results”, “reasons related to the physician (he never suggested it” [3.8% in 2016] or “he recommended against screening” [2.5% in 2016]), or “refusal to participate”, all dropped significantly between 2014 and 2016. Conclusions: The issue of “individual negligence” requires further analysis so as to clearly define the categories of individuals who remain unreceptive to screening and identify how best to involve them. The significant mention of “no risk factors” reveals ignorance of the fact that the colorectal cancer screening program actually targets all individuals in a given age group, regardless of individual risk factors. The decrease in reasons involving “fear" or related to the physician may be a result of awareness campaigns and GP mobilization.