Fig. 2

Receiver operating characteristic (ROC) curve analysis of the mucosa and submucosa thickness for detecting chronic acidosis. The best cut-off value is > 5.3 mm, (area under the ROC curve of 0.90: P < 0.0001; 95% c.i. 0.85 to 0.94; sensitivity 93%; specificity 76%; positive likelihood ratio 3.96; negative likelihood ratio 0.08). criterion: Youden index