Table 3.
Subgroup analysis | No. of cohorts | Pooled HR (95% CI) | P | Heterogeneity | P (meta regression) | |
---|---|---|---|---|---|---|
I2 | P | |||||
Sample size | 0.775 | |||||
<150 | 11 | 1.86 (1.31, 2.65) | 0.001* | 84.0% | < 0.001 | – |
≥150 | 7 | 1.61 (1.03, 2.51) | 0.037* | 85.0% | < 0.001 | – |
NOS score | 0.718 | |||||
<7 | 5 | 1.68 (1.02, 2.79) | 0.044* | 67.7% | 0.015 | – |
≥7 | 13 | 1.72 (1.34, 2.20) | < 0.001* | 85.6% | < 0.001 | – |
Region | 0.966 | |||||
Western country | 5 | 1.61 (0.94, 2.75) | 0.082 | 81.8% | < 0.001 | – |
Eastern country | 13 | 1.81 (1.32, 2.47) | 0.001* | 80.8% | < 0.001 | – |
Follow-up period | 0.378 | |||||
≥100 months | 11 | 1.49 (1.18, 1.87) | 0.001* | 79.7% | < 0.001 | – |
<100 months | 7 | 2.06 (1.44, 2.93) | 0.002* | 59.4% | 0.022 | – |
Source of HRs | 0.182 | |||||
Directly | 16 | 1.65 (1.32, 2.05) | < 0.001* | 84.3% | < 0.001 | – |
Indirectly | 2 | 3.89 (0.81, 18.75) | 0.091 | 61.9% | 0.105 | – |
Preoperative treatment | 0.543 | |||||
No | 14 | 1.62 (1.29, 2.05) | < 0.001* | 82.9% | < 0.001 | – |
Yes or unclear | 4 | 1.97 (1.13, 3.42) | 0.017* | 69.2% | 0.021 | – |
p < 0.05.