GOALS AND BACKGROUND This study aimed to compare differences in the fecal microbiota according to the risk of advanced colorectal neoplasia (ACN) based on a risk-score model in a large Korean cohort. STUDY Stool samples were collected from 1122 health screening recipients: 404 enrolled in the average risk (AR) group, 514 in the moderate risk (MR) group, and 204 in the high risk (HR) group, in accordance with their risk of ACN. The fecal microbiota was characterized using pyrosequencing of the V3-V4 region of the 16S rRNA genes. RESULTS The overall microbial diversity was significantly reduced with an increased risk of ACN [false discovery rate (FDR), P
