Table 2. Meta and subgroup analyses.
| Analysis | No. of studies | HR (95% CI) | P values for HR | I2 (%) | P value for heterogeneity |
|---|---|---|---|---|---|
| Overall survival | 7 | 1.88 (1.50–2.36) | <0.001 | 60.6 | 0.019 |
| TNM stage | |||||
| Advanced stage | 4 | 2.18 (1.80–2.65) | <0.001 | 0.0 | 0.926 |
| Mixed | 3 | 1.55 (1.15–2.11) | 0.004 | 55.8 | 0.104 |
| Treatment | |||||
| Mixed | 2 | 2.14 (1.73–2.65) | <0.001 | 0.0 | 0.875 |
| Surgery | 3 | 1.55 (1.15–2.11) | 0.004 | 55.8 | 0.104 |
| Chemoradiotherapy | 2 | 2.36 (1.51–3.68) | <0.001 | 0.0 | 0.587 |
| Disease-free survival/progression-free survival | 3 | 2.50 (1.20–5.20) | 0.014 | 58.2 | 0.092 |
| Cancer specific survival | 1 | 1.852 (1.185–2.915) | 0.007 | – | – |
TNM, tumor-node-metastasis; HR, hazard ratio; CI, confidence interval.