Comparison between non-erosive reflux disease (NERD) patients and GERD-free subjects.

CI, confidence interval; H. pylori, Helicobacter pylori; PG, pepsinogen; BMI, body mass index; y.o., years old. Chi-square test was used for statistical evaluation; the correlation of each subject background factor between NERD patients and GERD-free subjects was calculated respectively as an odds ratio (OR) with 95% confidence interval (CI). The level of significance in the univariate analyses was set at p value <0.05 (*).