Table 3.

Characteristics of included studies in the meta-analysis

Ref.	Country	Design	Group	Patients (n)	Male/female (n)	Mean age (yr)
Osugi et al[9]	Japan	Retro	R-Y	18	13/5	60.2
			B-I	25	12/13	64.7
Shinoto et al[10]	Japan	Retro	R-Y	20	NR	63 ± 12
			B-I	43	NR	63 ± 9
Nunobe et al[13]	Japan	Retro	R-Y	182	117/65	58.8
			B-I	203	127/76	58.7
Fukuhara et al[14]	Japan	Retro	R-Y	29	23/6	56.1
			B-I	41	19/22	66.0
Ishikawa et al[20]	Japan	RCT	R-Y	24	17/7	64 (43-80)
			B-I	26	19/7	61 (34-84)
Kojima et al[21]	Japan	Retro	R-Y	68	43/25	62.8 ± 12.2
			B-I	65	48/17	62.0 ± 8.9
Namikawa et al[22]	Japan	Retro	R-Y	38	22/16	71 (41-80)
			B-I	47	25/22	72 (33-86)
Tanaka et al[23]	Japan	Retro	R-Y	51	34/17	65.2
			B-I	50	34/16	66.2
Kumagai et al[24]	Japan	Retro	R-Y	95	74/21	62.7 (42-81)
			B-I	329	197/132	63.5 (29-90)
Kim et al[25]	South Korea	Retro	R-Y	26	21/5	≥ 60 (9)
			B-I	72	54/18	≥ 60 (41)
Lee et al[26]	South Korea	RCT	R-Y	47	28/19	58.5 ± 10.7
			B-I	49	31/18	60.0 ± 11.6
Imamura et al[27] or Hirao et al[31]	Japan	RCT	R-Y	169	115/54	63.9 ± 10.5
			B-I	163	105/58	64.4 ± 9.3

Retro: Retrospective observational study; RCT: Randomized controlled trial; R-Y: Roux-en-Y; B-I: Billroth-I.