Study	Reason for exclusion
Arguedas 2002	Non‐RCT
Bottger 1992	Non‐RCT
Byung 1997	Non‐RCT
Davids 1992a	Duplicate Davids 1992b
Dowsett 1989	Mostly hilar lesions
Dowsett 1989b	Duplicate Shepherd 1994
Dumonceau 2000	Metal stents only
Foco 1996	Non‐RCT
Groen 1987	Non‐RCT
Hatfield 1982	Intervention any biliary drainage
Hyoty 1990	Non‐RCT
Isayama 2000	Duplicate Isayama 2004
Knyrim 1992	Duplicate Knyrim 1993
Lawrie 1996	Delivery methods only of stent
Leung 1992	Non‐RCT , benign disease
Liliemoe 1999	Non‐RCT, surgery only
Linder 2005	Non‐RCT
Maosheng 2001	Non‐RCT
Martin 1997	Duplicate of England 2000
Matasuda 1991	Non‐RCT
Pedersen 1993	Non‐RCT
Pedersen 1998	Non‐RCT
Prat 2004	Non‐RCT
Raikar 1996	Non‐RCT
Rosch 1998	Non‐RCT
Scholf 1994	Non‐RCT
Sciume 2004	Contains patients with benign disease
Siegel 1986	Non‐RCT
Sonnenfeld 1986	Non‐RCT
Suih 2000	Metal only
Sung 1993	Benign disease
Sung 1994	Non‐RCT
van Berkel 2005	Non‐RCT
Wagner 1993	Hilar lesions only
Wasan 2004	Surgically resectable