The overall incidence of PEP was 6.3 % ( 10/159 ) and no significant differences were observed between ulinastatin and nafamostat groups in terms of the incidences of PEP ( 1.9 % and 3.8 % , P = 0.560 ) , hyperamylasemia , hyperlipasemia , and abdominal pain , although these were significantly lower than those of the control group ( P < 0.001 ) .