Correlation between fecal immunochemical test results and the Mayo endoscopic subscores. There was a significant positive correlation between fecal hemoglobin concentrations and the MES (Spearman rank correlation coefficient = 0.6530, P < 0.0001). The proportion of cases with negative FIT results (fecal hemoglobin concentration ≤ 100 ng/mL) was greatest in cases with an MES of 0 (88/94, 92%). The proportion decreased gradually as the MES increased (MES 1: 16/57, 28%, MES 2: 6/39, 15%), and the trend of the decrease in relation to the MES was statistically significant (P < 0.0001, Cochran-Armitage trend test).