Predictors of the technical success of ultrasound-guided percutaneous transhepatic biliary drainage for biliary obstruction

Table 5 Bedside scoring system for predicting the probability of successful percutaneous transhepatic biliary drainage

Predictor	Points assigned if:	Points
Operator experience	More experience	2
Dedicated probe	Specialized probe used	3
Procedural cooperation	Good cooperation	3
Bile duct diameter	≥ 6 mm	2
Serum bilirubin	> 340 μmol/L	3
Operator seniority	High title	1
Total score		0-14
Predicted success probability	Corresponding score range
Low	0-4
Intermediate	5-9
High	10-14

Points are assigned based on the regression coefficients and clinical weight. Operator seniority, while not statistically significant in the multivariate model (P = 0.207), was included due to its established clinical relevance in procedural settings.