Table 3. Plastic versus self-expanding metal stents for hilar lesions.

Study (year)	Plastic	SEMS	p-value	Ref.
Knyrim et al. (1993)	Median patency: 5 months Cholangitis incidence 36%	Median patency: 5 months Cholangitis incidence 15%	NS <0.05	[20]
Perdue et al. (2008)	Complication rate at day 30: 32.1% Adverse outcome: 39%	Complication rate at day 30: 8.8% Adverse outcome: 12%	0.027 0.017	[29]
Raju et al. (2011)	Median patency: 1.86 months Complication rate: 7.7%	Median patency: 5.56 months Complication rate: 8.3%	<0.0001 0.79	[30]
Sangchan et al. (2012)	Successful drainage: 46.3% Complication rate: 33.3%	Successful drainage: 70.4% Complication rate: 46.3%	0.011 0.246	[31]
Liberato et al. (2012)	Median patency: 20 weeks Complication rate: 56.4%	Median patency: 27 weeks Complication rate: 24.4%	<0.0001 <0.001	[32]

NS: Not significant; SEMS: Self-expanding metal stents.