Table 4.

Comparison of pain level between the two groups, n (%)

	Pain-free/mild pain		Moderate/severe pain		Difference, % (95%CI)	P value
	Double-stent group	Single-stent group	Double-stent group	Single-stent group
Preoperative	39 (97.5)	36 (94.7)	1 (2.5)	2 (5.3)	0.056 (0.175, 0.063)	0.610
After 1 week	38 (95)	35 (92.1)	2 (5)	3 (7.9)	0.058 (0.207, 0.091)	0.671
After 1 month	37 (92.5)	31 (81.6)	3 (7.5)	7 (18.4)	0.218 (-0.407, -0.029)	0.187
After 2 months	38 (95)	26 (68.4)	2 (5)	12 (31.6)	0.532 (-0.711, -0.353)	0.003
After 3 months	38 (95.0)	18 (47.4)	2 (5.0)	20 (52.6)	0.85 (0.7304, 0.9656)	< 0.001
After 6 months	31 (77.5)	6 (15.8)	9 (22.5)	32 (84.2)	0.13 (1.0185, 1.4495)	< 0.001

Pain-free/mild pain: Visual analog scale (VAS) scores ≤ 3. Moderate/severe pain: VAS scores > 3. The double-stent group underwent endoscopic retrograde cholangiopancreatography with a fully-covered self-expandable metallic biliary stent and a pancreatic duct stent, while the single-stent group underwent a fully-covered self-expandable metallic biliary stent only.