Network meta-analysis of randomized controlled trials on esophagectomies in esophageal cancer: The superiority of minimally invasive surgery

Table 1 Baseline characteristics of the included studies

Ref.	Year	Country	Design	Compared interventions	Number of patients	Male/female ratio	Age in yr, mean	Squamous cell cancer/adenocarcinoma ratio	Inclusion criteria
Straatman et al[25]	2012	Netherlands, Spain, Italy	Multicenter	MI-TT	59-56	43/16-46/17	62.3–61.8	24/35-19/36	cT1-3, N0-1, M0
van der Sluis et al[26]	2019	Netherlands	Single center	RA-TT	54-55	46/8-42/13	64-65	13/41-12/43	T1-4a, N0-3, M0
Mariette et al[27]	2019	France	Multi center	H-TT	103-104	88/15-175/32	59-61 (median)	46/57-84/123	T1-3, N0-1, M0
Guo et al[28]	2013	China	Single center	MI-TT	111-110	68/43-72/38	57.3-60.8	No information	T1-3, N0-1, M0
Ma et al[29]	2018	China	Single center	MI-TT	47-97	36/11-83/14	61-59.3	43/0-91/2	Resectable cancer
Jacobi et al[30]	1997	Germany	Single center	TH-TT	16-16	No information	54-55	13/3-13/3	Resectable cancer
Goldminc et al[31]	1993	Australia	Single center	TH-TT	32-35	31/1-33/2	57.4-57.4	32/0-35/0	Resectable squamous cell cancer
Chu et al[32]	1997	China	Single center	TH-TT	20-19	18/2-17/2	60.7-63.9	No information	Lower third resectable cancer
Hulscher et al[33]	2002	Netherlands	Multicenter	TH-TT	106-114	92/14-97/17	69-64	0/106-0/114	Resectable adenocarcinoma
Yang et al[35]	2016	China	Single center	MI-TT	120-120	82/38-87/33	62.5 -67.8	75/45-72/48	T1-3, N0-1, M0
Paireder et al[34]	2018	Austria	Single center	H-TT	14-12	10/4-10/2	64.5-62.5 (median)	4/10-1/11	Siewert I-II, resectable squamous cell cancer

Number of patients, male/female ratio, age, and ratio of squamous cell cancer and adenocarcinoma are presented according to the compared interventional arms. H: Hybrid esophagectomy; MIE: Minimally invasive esophagectomy; RA: Robot assisted esophagectomy; TH: Transhiatal esophagectomy; TT: Transthoracic esophagectomy.

Table 2 The results of the risk of bias assessment by each domain

Ref.	Randomization process	Deviation from intended intervention	Missing outcome data	Measurement of the outcome	Selection of the reported results	Overall
Straatman et al[25]	Low risk	Low risk	Low risk	Low risk	Low risk	Low risk
van der Sluis et al[26]	Low risk	Low risk	Low risk	Low risk	Low risk	Low risk
Mariette et al[27]	Low risk	Low risk	Low risk	Low risk	Low risk	Low risk
Guo et al[28]	Unclear risk	Low risk	Low risk	Low risk	Unclear risk	Unclear risk
Ma et al[29]	Unclear risk	Unclear risk	Low risk	Low risk	Unclear risk	High risk
Jacobi et al[30]	Unclear risk	Unclear risk	Low risk	Low risk	Unclear risk	High risk
Goldminc et al[31]	Unclear risk	Unclear risk	Low risk	Low risk	Low risk	Unclear risk
Chu et al[32]	Unclear risk	Unclear risk	Low risk	Low risk	Unclear risk	High risk
Hulscher et al[33]	Low risk	Unclear risk	Low risk	Low risk	Unclear risk	Unclear risk
Yang et al[35]	Unclear risk	Unclear risk	Low risk	Low risk	Unclear risk	High risk
Paireder et al[34]	Low risk	Unclear risk	Low risk	Low risk	Unclear risk	Unclear risk

Risk of bias is indicated according to each domain of the Revised Cochrane risk-of-bias tool for randomized trials[23]. By the assessment of overall risk of bias, low risk of bias was given in the case of low risk of bias by every domain; if one or two domains were assessed as unclear risk of bias, unclear overall risk of bias was given, and if at least three domains were accompanied with unclear risk of bias, the overall risk of bias was assessed as high risk of bias.