Table 2. Outcomes of the meta-analysis.
Parameters | No. Studies | Sample Size | Heterogeneity | OR | 95% CI of Overall Effect | P | |
CIMP+ | CIMP− | ||||||
H. pylori | 5 | 137 | 243 | P = 0.05, I2 = 58% | 2.23 | 1.25–4.00 | P = 0.007 |
EBV | 2 | 40 | 104 | P = 0.39, I2 = 0% | 51.27 | 9.39–279.86 | P<0.00001 |
MSI | 4 | 136 | 306 | P = 0.01, I2 = 71% | 4.44 | 1.17–16.88 | P = 0.03 |
Age | 4 | 87 | 195 | P = 0.52, I2 = 0% | 1.10 | 0.63–1.93 | P = 0.74 |
Gender | 9 | 184 | 565 | P = 0.91, I2 = 0% | 0.69 | 0.48–1.00 | P = 0.05 |
Tumor site | 4 | 85 | 206 | P = 0.17, I2 = 40% | 0.85 | 0.51–1.44 | P = 0.55 |
Pathological type | 7 | 142 | 440 | P = 0.03, I2 = 56% | 0.63 | 0.31–1.28 | P = 0.20 |
Cell differentiation | 3 | 45 | 264 | P = 0.68, I2 = 0% | 0.64 | 0.29–1.42 | P = 0.27 |
TNM stage | 4 | 47 | 212 | P = 0.08, I2 = 56% | 1.39 | 0.54–3.57 | P = 0.49 |
Distant metastasis | 4 | 103 | 258 | P = 0.004, I2 = 77% | 1.69 | 0.37–7.67 | P = 0.49 |
Lymph node metastasis | 6 | 128 | 349 | P = 0.16, I2 = 37% | 0.81 | 0.50–1.31 | P = 0.39 |
5-year survival | 2 | 32 | 114 | P = 0.02, I2 = 82% | 0.65 | 0.04–10.70 | P = 0.76 |
CIMP, CpG island methylator phenotype; CI, confidence interval; EBV, Epstein-Barr virus; H. pylori, Helicobacter pylori; MSI, microsatellite instability; OR, odds ratio.