Mini-invasive vs open resection of colorectal cancer and liver metastases: A meta-analysis

Table 1 Characteristics of the included studies

Author-year	Country	Study type	Gender (M/F)		BMI (kg/m2)2		Age (yr)2		Qualityscore3
			MIS	OS	MIS	OS	MIS	OS
Chen-2011	China	Retrospective	18/5	14/4	NR	NR	55 ± 10	53 ± 9	8
Chen-2019	China	Retrospective	10/6	9/13	23.8 ± 3.7	23.3 ± 4.1	66.0 ± 10.4	64.8 ± 13.0	7
Gorgun-2017	America	Retrospective	6/8	16/13	25.1 ± 0.8	27.5 ± 1.2	56.3 ± 3.3	57.7 ± 2.5	7
Hu-2012	China	Matched-pair	10/3	9/4	21.5 ± 7.8	22.2 ± 8.4	54.0 ± 10.0	53.0 ± 11.0	8
Ivanecz-2017	Slovenia	Matched-pair	6/4	6/4	26.9 (23.6-32.1)	24.0 (23.1-25.5)	62.2 ± 7.9	65.4 ± 8.1	9
Lin-2015	China	Matched-pair	5/2	21/15	21.9 ± 2.2	21.2 ± 1.6	59.6 ± 3.4	57.4 ± 10.4	7
Ma-2018	China	Matched-pair	9/3	8/4	23.0 (19.3-26.7)	21.6 (75.5-24.9)	3/91	1/111	8
Ratti-2016	Italy	Matched-pair	14/11	27/23	NR	NR	60 (37-80)	62 (35-81)	8
Takasu-2014	Japan	Matched-pair	3/4	3/4	NR	NR	74.0 ± 12.0	62.0 ± 4.0	7
Tranchart-2016	France	Matched-pair	42/47	40/49	24.0 ± 3.6	24.7 ± 2.5	66.6 ± 10.8	65.0 ± 9.4	7

¹Dichotomous variables, >60/≤60 years;

²The data are expressed as the mean ± SD or medians (range);

³According to the Newcastle-Ottawa scale classification. BMI: Body mass index; F: Female; M: Male; MIS: Minimally invasive surgery; OS: Open surgery; NR: Not reported.