Table 2. Main results of subgroup analyses.

Categories	Subgroups	n	HR (95% CI)	P	Heterogeneity
					I2 (%)	Ph
All		13	1.18(0.86–1.63)	0.310	78.40	0.00
Ethnicity	Asian	4	2.33(1.35–4.00)	0.002	57.50	0.07
	Caucasians	9	0.88(0.68–1.15)	0.358	61.90	0.01
Follow-up	≤ 60	5	2.29(1.50–3.51)	<0.001	43.40	0.10
	> 60	8	0.81(0.64–1.03)	0.090	51.90	0.06
Expression level	Increased in tumors	12	1.26(0.89–1.77)	0.190	78.40	0.00