Table 2.
Relative risks (RRs) and 95% confidence intervals (CIs) for sensitivity analysis.
| No. of studies | CC (colon cancer) | RCC (right-sided colon cancer) | LCC (left-sided colon cancer) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| RR (95%CI) | I2,% | P heterogeneity | P value for interaction | RR (95%CI) | I2,% | P heterogeneity | P value for interaction | RR (95%CI) | I2,% | P heterogeneity | P value for interaction | ||
| Geographical area | |||||||||||||
| USA | 6 | 1.29 (1.16-1.42) | 43.5 | 0.115 | 0.156 | 1.36 (1.18-1.56) | 51.2 | 0.069 | 0.837 | 1.19 (1.08-1.31) | 0 | 0.953 | 0.732 |
| Europe | 4 | 1.28 (1.12-1.47) | 29.7 | 0.234 | 1.39 (1.20-1.60) | 0 | 0.774 | 1.13 (0.84-1.51) | 59.7 | 0.059 | |||
| Sex | |||||||||||||
| Males | 5 | 1.24 (1.10-1.40) | 32.5 | 0.205 | 0.025 | 1.30 (1.17-1.45) | 0 | 0.445 | 0.600 | 1.15 (1.01-1.31) | 0 | 0.444 | 0.682 |
| Females | 5 | 1.28 (1.05-1.57) | 68.6 | 0.013 | 1.39 (1.10-1.77) | 66.5 | 0.018 | 1.09 (0.87-1.37) | 30.6 | 0.217 | |||
| Definition of RCC and LCC | |||||||||||||
| Definition 1 | 8 | 1.32 (1.20-1.46) | 33.4 | 0.162 | 0.156 | 1.40 (1.22-1.60) | 40.4 | 0.109 | 0.548 | 1.21 (1.09-1.35) | 0 | 0.957 | 0.362 |
| Definition 2 | 2 | 1.21 (1.03-1.41) | 56.9 | 0.128 | 1.33 (1.20-1.47) | 0 | 0.914 | 0.98 (0.63-1.53) | 83.0 | 0.015 | |||
| Duration of follow-up | |||||||||||||
| < 15 years | 5 | 1.29 (1.20-1.38) | 16.3 | 0.311 | 0.156 | 1.35 (1.21-1.51) | 34.5 | 0.191 | 0.904 | 1.21 (1.10-1.33) | 0 | 0.902 | 0.321 |
| ≥ 15 years | 5 | 1.26 (1.07-1.48) | 49.9 | 0.092 | 1.37 (1.15-1.62) | 28.5 | 0.232 | 1.07 (0.86-1.34) | 32.4 | 0.206 | |||
| Level of adjustment | |||||||||||||
| Age-adjusted | 5 | 1.30 (1.15-1.47) | 31.8 | 0.209 | 0.175 | 1.33 (1.15-1.54) | 22.2 | 0.273 | 0.947 | 1.24 (1.10-1.40) | 0 | 0.799 | 0.685 |
| Multi-adjusted | 5 | 1.28 (1.11-1.48) | 39.6 | 0.157 | 1.32 (1.11-1.58) | 35.5 | 0.184 | 1.19 (1.05-1.36) | 0 | 0.863 | |||