Table 2.
The prognostic significance of Epstein-Barr virus infection in gastric cancer by prespecified study characteristics in different subgroups
| Stratified analysis | No. of Studies | Test of association | Test of heterogeneity | |||||
|---|---|---|---|---|---|---|---|---|
| Pooled HR (95 % CI) | Z | P-value | Model | X 2 | P-value | I2 (%) | ||
| Overall | 24 | 0.67 (0.55,0.79) | 11.18 | <0.001 | fixed-effects model | 26.39 | 0.283 | 12.8 |
| Region | ||||||||
| Asia | 13 | 0.62 (0.48,0.75) | 9.18 | <0.001 | fixed-effects model | 19.65 | 0.074 | 38.9 |
| Europe | 5 | 0.87 (0.52,1.23) | 4.87 | <0.001 | fixed-effects model | 1.37 | 0.85 | 0 |
| Americas | 6 | 0.93 (0.53,1.34) | 4.53 | <0.001 | fixed-effects model | 1.76 | 0.881 | 0 |
| Statistical methodology | ||||||||
| Univariate analysis | 21 | 0.62 (0.50,0.74) | 9.81 | <0.001 | fixed-effects model | 18.52 | 0.553 | 0 |
| Multivariate analysis | 3 | 1.13 (0.76,1.50) | 5.95 | <0.001 | fixed-effects model | 1.36 | 0.506 | 0 |
| Quality assessment | ||||||||
| High quality | 21 | 0.67 (0.55,0.79) | 10.93 | <0.001 | fixed-effects model | 25.77 | 0.174 | 22.4 |
| Low quality | 3 | 0.83 (0.16,1.51) | 2.41 | 0.016 | fixed-effects model | 0.4 | 0.819 | 0 |
Abbreviations: EBV Epstein - Barr virus, HR hazard ratio, CI confidence interval