“…[23][24][25][26][27] Proponents advocate routine PBD in an attempt to reduce the incidence of hepatic dysfunction and perioperative complications in patients with obstructive jaundice, [28][29][30][31] while opponents consider that it does not significantly reduce postoperative complications and mortality, [32][33][34] can even result in major complications that can delay surgery and increase hospital costs, [35][36][37] and therefore should not be performed routinely. [13,[37][38][39][40][41][42][43][44][45][46][47][48] We have noted that almost all the above studies on the effects of PBD have the following limitations and methodological flaws: (i) most patient data were collected retrospectively, so there is a risk of selection bias; [44,47,48] (ii) in some studies, no distinction was made between different levels of biliary obstruction; [48][49][50] (iii) in many studies, no distinction was made between different types of operations; [36,44,48,51] (iv) often no distinction was made between different methods and durations of PBD; [45,47,49,52] and (v...…”