Table 2.
Subgroup meta-analysis of pooled hazard ratios for overall survival.
| Subgroup analysis | No. of studies | No. of patients | HR (95% CI) random | Significance (P value) | Heterogeneity I2 (%), P value |
|---|---|---|---|---|---|
| Sample size | |||||
| ≥60 | 11 | 867 | 1.86 (1.39, 2.51) | <0.001 | 78.9%, 0.000 |
| <60 | 11 | 472 | 1.71 (1.48, 1.97) | <0.001 | 0.0%, 0.742 |
|
| |||||
| Survival analysis method | |||||
| Multivariate | 4 | 382 | 1.91 (1.20, 3.04) | 0.006 | 82.7%, 0.001 |
| Univariate | 18 | 957 | 1.79 (1.49, 2.14) | <0.001 | 52.0%, 0.006 |
|
| |||||
| Follow-up (months) | |||||
| >60 | 8 | 478 | 2.13 (1.50, 3.01) | <0.001 | 72.1%, 0.001 |
| ≤60 | 14 | 861 | 1.70 (1.40, 2.07) | <0.001 | 58.0%, 0.003 |
|
| |||||
| Tumor type | |||||
| Gastric cancer | 4 | 245 | 1.74 (1.35, 2.24) | <0.001 | 0.0%, 0.892 |
| Cervical cancer | 2 | 150 | 2.37 (1.68, 3.35) | <0.001 | 0.0%, 0.346 |
| HCC | 2 | 98 | 1.99 (1.32, 3.00) | 0.001 | 0.0%, 0.676 |
| Glioma | 2 | 119 | 2.78 (1.55, 4.97) | 0.001 | 41.4%, 0.192 |
| Colorectal cancer | 2 | 113 | 1.74 (0.98, 3.09) | 0.057 | 44.4%, 0.180 |
| Osteosarcoma | 2 | 95 | 1.82 (1.23, 2.70) | 0.003 | 6.2%, 0.302 |
| DLBCL | 1 | 80 | 1.23 (1.09, 1.39) | 0.001 | - |
| NPC | 1 | 129 | 3.02 (1.53, 5.94) | 0.001 | - |
| Ovarian cancer | 1 | 24 | 2.82 (1.39, 5.73) | 0.004 | - |
| RCC | 1 | 20 | 2.56 (1.04, 6.30) | 0.041 | - |
| ESCC | 1 | 85 | 0.65 (0.43, 0.99) | 0.043 | - |
| NSCLC | 1 | 40 | 1.42 (1.02, 1.97) | 0.037 | - |
| Prostate cancer | 1 | 56 | 1.61 (1.07, 2.43) | 0.024 | - |
| Breast cancer | 1 | 85 | 1.90 (1.12, 3.22) | 0.017 | - |
Abbreviations: HCC: hepatocellular carcinoma; DLBCL: diffuse large B cell lymphoma; NPC: nasopharyngeal carcinoma; RCC: renal cell carcinoma; ESCC: esophageal squamous cell carcinoma; NSCLC: non-small-cell lung cancer; HR: hazard ratio.