Figure 3.

KAP of the non-PSC and PSC ERCP procedures across the endoscopists (the endoscopists #1–9 were from Center 1, #10–16 from Center 2, #17 from Center 3, and #18–20 from Center 4, respectively). A logarithmic scale is used on the y-axis to better delineate the changes at low dose levels. In the boxplots, circles and asterisks denote outliers and extreme cases, respectively. Outliers are defined as data points that fall beyond 3 standard deviations from the mean. Extreme cases are identified as data points lying outside of 1.5 times the interquartile range above the third quartile or below the first quartile in the boxplot.