Figure 2  .

Common bile duct (CBD) pressure (A), sphincter of Oddi (SO) basal and peak pressures (B, C), and SO contraction frequency (D) before (Pre), one week after, and one year after endoscopic papillary balloon dilation (EPBD) in patients with CBD stones. Data are expressed by the outlier box plot generated by JMP v. 4 software. The box represents the 25th and 75th quantiles (quartiles), with the line in the middle of the box identifying the median; the broken lines indicate the upper quartile +1.5× (interquartile range) and the lower quartile −1.5× (interquartile range), respectively. *p<0.05, **p<0.01.