Table 2. Subgroup analysis of the meta-analysis.

Subgroup	Number of studies	Pooled HR	95% CI		P	Medol	I2	P
Region
Asia	9	2.745	2.030	3.711	< 0.001	Fixed effect	0.0%	0.565
non-Asia	5	2.066	1.838	2.321	< 0.001	Fixed effect	0.0%	0.730
Treatment
Surgery	9	2.055	1.587	2.660	< 0.001	Fixed effect	0.0%	0.620
non-Surgery	5	2.163	1.919	2.439	< 0.001	Fixed effect	25.6%	0.251
Analysis of survival
Multivariate	11	2.140	1.912	2.394	< 0.001	Fixed effect	0.0%	0.802
Survival curve	3	2.692	1.210	5.992	0.015	Random effect	64.1%	0.062

HR: hazard ratio.