Efficacy and safety of double-balloon enteroscopy-assisted endoscopic retrograde cholangiopancreatography in surgically altered anatomy: A systematic review and meta-analysis

Table 2 Quality evaluation of the eligible studies with Newcastle-Ottawa scale

Ref.	Selection	Comparability	Outcome
Cheng et al[26]	4	1	3
Tsou et al[58]	4	2	3
Tomoda et al[59]	4	2	2
Liu et al[60]	4	2	2
Tsutsumi et al[61]	4	1	2
Mizukawa et al[62]	4	2	3
Yamada et al[63]	4	2	3
Zamora Nava et al[64]	4	2	2
Farina et al[65]	4	2	3
Yokoyama et al[66]	4	2	2