Table 2. Pooled hazard ratios for OS according to subgroup analyses.

Outcome subgroup	No. of patients	No. of studies	HR (95% CI)	P value	Model	heterogeneity
						I2 (%)	P
Overall survival	6278	25	2.13(1.69–2.69)	<0.001	random	88.7%	<0.001
Ethnicity
Asian	1206	6	2.22(1.27–3.87)	0.005	random	86.4%	<0.001
Caucasian	5072	19	2.06(1.73–2.44)	<0.001	random	54.3%	0.003
Cut-off value
1.5ULN	4414	13	1.96(1.43–2.68)	<0.001	random	87.9%	<0.001
Others	1864	12	2.21(1.73–2.83)	<0.001	random	59.4%	0.004
Analysis type
Multivariate	5016	21	2.11(1.63–2.71)	<0.001	random	89%	<0.001
Univariate	1262	4	1.98(1.52–2.56)	<0.001	fixed	43.3%	0.152
Tumor type
All stage	1159	5	2.41(1.09–5.33)	0.03	random	77.8%	0.001
Metastasis	4686	18	2.02(1.57–2.59)	<0.001	random	89.3%	<0.001
Non-metastasis	433	2	3.67(1.33–10.13)	0.012	random	52.8%	0.146

Abbreviation: OS = overall survival; HR = hazard ratio; CI = confidence interval.