Table 2 Subgroup analysis and sensitivity analyses on primary outcomes
Subgroup | No. of studies | No. of patients | OR | 95%CI | I2 | P-value |
|---|---|---|---|---|---|---|
Type of studies | ||||||
CS | 2 | 46 | 12.97 | 2.29–73.50 | 76% | 0.004 |
CCS | 5 | 281 | 5.74 | 2.73–12.05 | 0% | < 0.001 |
Intervention | ||||||
Dissection or non-dissection | 3 | 188 | 5.66 | 2.42–13.24 | 0% | < 0.001 |
R0 resection or not | 3 | 111 | 11.98 | 3.12–46.07 | 47% | < 0.001 |
Synchronous or metachronous | ||||||
Synchronous | 2 | 135 | 5.21 | 1.69–16.07 | 0% | 0.004 |
Metachronous | 1 | 38 | 6.20 | 0.33–115.92 | NA | NA |
Both | 3 | 135 | 5.81 | 2.25–15.01 | 0% | 0.0003 |
Country | ||||||
Korea | 4 | 207 | 7.60 | 3.46–16.71 | 36% | < 0.001 |
Japan | 3 | 120 | 5.34 | 1.48–19.25 | 0% | < 0.001 |
Location of tumor | ||||||
Left-sided | 3 | 111 | 11.98 | 3.12–46.07 | 47% | 0.0003 |
All | 4 | 216 | 5.24 | 2.36–11.67 | 0% | < 0.001 |