## 2 Materials and Methods
### Selection of Patients
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Characteristics** & **All Group (N = 403)** & **Without PEP (n = 368)** & **With PEP (n = 35)** & _p-Value_ \\ \hline Age, years, median (quartile) & 66 (55–75) & 66 (54–75) & 68 (59–79) & 0.215 \\ \hline Gender, female/male, n (\%) & 237/166 (58.8/41.2) & 218/150 (59.2/40.8) & 19/16 (54.3/45.7) & 0.569 \\ \hline Environment, urban/ruval, n (\%) & 226/177 (56.1/43.9) & 210/158 (45.7/54.3) & 16/19 (57.1/42.9) & 0.196 \\ \hline Personal history of ERCP procedures & & & & \\ Personal history of ERCP procedures, n (\%) & 81 (20.1) & 79 (21.5) & 2 (2.5) & 0.011 \\ Presence of in situ biliary stents, n (\%) & 33 (8.2) & 33 (8.97) & 0 (0) & 0.012 \\ \hline Type of indication & & & & \\ urgent/electric, n (\%) & 119/284 (29.5/70.5) & 110/258 (29.9/70.1) & 9/26 (25.7/74.3) & 0.597 \\ curative/palliative, n (\%) & 355/48 (88.1/11.9) & 328/40 (89.1/10.9) & 27/8 (77.1/22.9) & 0.036 \\ \hline Anatomy of the major papilla & (N = 322) & (n = 289) & (n = 33) \\ anatomic, n (\%) & 168 (52.2) & 150 (51.9) & 18 (54.5) & 0.082 \\ Tip I, n (\%) & 36 (11.2) & 31 (10.7) & 5 (15.2) & 0.025 \\ Tip II, n (\%) & 61 (18.9) & 59 (20.4) & 2 (6.1) & 0.001 \\ Tip III, n (\%) & 32 (9.9) & 31 (10.7) & 1 (3) & 0.001 \\ Tip IV, n (\%) & 25 (7.8) & 18 (6.2) & 7 (21.2) & 0.001 \\ \hline Duoderal diverticula, n (\%) & & & & \\ Absent & 352 (87.3) & 320 (87) & 32 (91.4) & 0.425 \\ Tip 1 & 8 (2) & 8 (2.2) & 0 (0) & 0.067 \\ Tip 2 & 32 (7.9) & 30 (8.2) & 2 (5.7) & 0.092 \\ Tip 3 & 11 (2.7) & 10 (2.7) & 1 (2.9) & 0.846 \\ \hline ASA classification, n (\%) & & & & \\
1 & 236 (58.6) & 217 (59) & 19 (54.3) & 0.461 \\
2 & 138 (34.2) & 127 (34.5) & 11 (31.4) & 0.537 \\
3 & 21 (5.2) & 16 (4.3) & 5 (14.3) & 0.064 \\
4 & 8 (2) & 8 (2.2) & 0 (0) & 0.077 \\ \hline Cannulation, easy/difficult, n (\%) & 285/118 (70.7/29.3) & 271/97 (73.6/26.4) & 14/21 (40/60) & \textless{}0.001 \\ \hline Number of cannulation attempts, \(\leq\)5/\(>\)5, & 316/87 (78.4/21.6) & 295/73 (80.2/19.8) & 21/14 (60/40) & 0.009 \\ \hline Cannulation time: \(<\)5 min/\(\geq\)5 min, n (\%) & 337/66 (83.6/16.4) & 316/52 (85.9/14.1) & 21/14 (60/40) & \textless{}0.001 \\ \hline Type of cannulation & & & & \\ \hline Wirsung cannulation, n (\%) & 73 (18.1) & 60 (16.3) & 13 (37.1) & 0.005 \\ CBP cannulation CBP, n (\%) & 365 (90.6) & 333 (90.5) & 32 (91.4) & 0.903 \\ Guide write cannulation, n (\%) & 363 (90.1) & 329 (89.4) & 34 (97.1) & 0.242 \\ SC cannulation, n (\%) & 10 (2.5) & 9 (2.4) & 1 (2.9) & 0.675 \\ Selective cannulation, n (\%) & 346 (85.9) & 316 (85.9) & 30 (85.7) & 0.819 \\ \hline Sphincterotomy & & & & \\ \hline Without sphincterotomy, n (\%) & 91 (22.9) & 88 (23.9) & 3 (8.6) & 0.021 \\ Partial biliary sphincterotomy, n (\%) & 134 (33.3) & 120 (32.3) & 14 (40) & 0.053 \\ Total biliary sphincterotomy, n (\%) & 178 (44.2) & 160 (43.5) & 18 (51.4) & 0.089 \\ Needle knife precut, n (\%) & 25 (6.2) & 17 (4.6) & 8 (22.9) & 0.002 \\ Needle inife fistulotomy, n (\%) & 4 (1) & 4 (1.1) & 0 (0) & 0.163 \\ Trans-pancreatic, n (\%) & 10 (2.5) & 9 (2.4) & 1 (2.9) & 0.841 \\ \hline SIRS & 66 (16.4) & 54 (14.7) & 12 (34.3) & 0.002 \\ \hline With suspicion of organ dysfunction & & & & \\ (qSOFA) & 48 (11.9) & 39 (10.6) & 9 (25.7) & 0.008 \\ \hline qSOFA 1 & 27 (6.7) & 23 (6.3) & 4 (11.4) & 0.017 \\ qSOFA 2 & 12 (3) & 9 (2.5) & 3 (8.6) & 0.018 \\ qSOFA 3 & 9 (2.2) & 7 (1.9) & 2 (5.7) & 0.014 \\ \hline Organ dysfunction & 40 (9.9) & 32 (8.7) & 8 (22.9) & 0.007 \\ \hline one dysfunction & 35 (8.7) & 29 (7.9) & 6 (17.1) & \textless{}0.001 \\ two dysfunctions & 3 (0.7) & 3 (0.8) & 0 (0) & 0.154 \\ three dysfunctions & 2 (0.5) & 0 (0) & 2 (5.7) & 0.003 \\ \hline Duration of hospitalization, days, median & & & & \\ (quartile) & 11 (7–17) & 11 (7–17) & 13 (10–22) & 0.007 \\ \hline \hline \end{tabular}
\begin{tabular}{c c c c} \hline \hline
**P**EP: post-endoscopic pancreatitis; SD—standard deviation. SIRS: systemic inflammatory response syndrome (SIRS). qSOFA: quick Sequential Organ Failure Assessment.  
\end{table}