Table 2. Summary of meta-analysis results.

Factors	No. of studies	No. of patients	Effects model	HR(95% CL)	P	Heterogeneity
						I2(%)	Ph
Overall survival (OS)
Overall	16	4910	Random	1.50 (1.27-1.77)	< 0.001	80.2%	< 0.001
Ethnicity:
Caucasian	5	1269	Random	1.36 (0.99-1.87)	0.058	72.0%	0.006
Asian	11	3641	Random	1.69 (1.31-2.21)	< 0.001	83.5%	< 0.001
Sample size:
<200	8	1605	Random	2.29 (1.49-3.52)	< 0.001	69.4%	0.002
≥200	8	3305	Random	1.23 (1.07-1.41)	0.002	69.6%	0.002
Histologic types:
Epithelial	8	2622	Random	1.28 (1.09-1.50)	0.003	71.8%	0.001
Mixed	8	2288	Random	1.93 (1.35-2.77)	< 0.001	77.9%	< 0.001
Cut-off value:
<3.4	7	2600	Random	1.30 (1.05-1.61)	0.014	60.9%	0.018
≥3.4	9	2310	Random	1.89 (1.35-2.65)	< 0.001	86.2%	< 0.001
NOS score:
<7	7	1775	Random	1.49 (1.24-1.68)	0.005	70.7%	0.002
≥7	9	3135	Random	1.66 (1.24-2.22)	0.001	84.5%	< 0.001
Progression free survival (PFS)
Overall	12	3884	Random	1.53 (1.28-1.84)	< 0.001	85.2%	< 0.001
Ethnicity:
Caucasian	3	515	Fixed	1.25 (1.10-1.42)	0.001	27.5%	0.252
Asian	9	3369	Random	1.59 (1.25-1.84)	< 0.001	88.0%	< 0.001
Sample size:
<200	6	1333	Random	1.83 (1.24-2.69)	0.002	73.1%	< 0.001
≥200	6	2551	Random	1.35 (1.13-1.62)	0.001	83.0%	< 0.001
Histology type:
Epithelial	6	2350	Random	1.32 (1.09-1.59)	0.005	83.5%	< 0.001
Non-epithelial	6	1534	Random	2.07 (1.39-3.01)	< 0.001	75.4%	0.001
Cut-off value:
<3.4	6	2408	Fixed	1.28 (1.17-1.40)	< 0.001	29.9%	0.211
≥3.4	6	1476	Random	2.09 (1.30-3.37)	< 0.001	90.5%	< 0.001
Analysis method:
Univariate	2	377	Fixed	1.09 (1.06-1.12)	< 0.001	0.0%	0.768
Multivariate	10	3507	Random	1.43 (1.19-1.71)	< 0.001	84.4%	< 0.001
NOS score:
<7	6	1256	Random	1.57 (1.15-2.15)	0.005	68.4%	0.007
≥7	6	2628	Random	1.54 (1.18-2.01)	0.001	88.8%	< 0.001

P denotes P value for statistical significance based on Z test; Ph denotes P value for heterogeneity based on Q test. HR hazard ratio; CI confidence interval.