Table 3. Subgroup analyses of the association between cholecystectomy and the risk of colorectal cancer, stratified by tumor location.
| Subgroup | RR (95% CI) | Test for overall effect (P value) | No. of studies | Heterogeneity I2, % |
|---|---|---|---|---|
| CC | 1.08 (0.98–1.19) | 0.112 | 16 | 76.5 |
| Left-sided | 1.02 (0.88–1.18) | 0.836 | 8 | 67.0 |
| Right-sided | 1.20 (1.04–1.38) | 0.010 | 9 | 64.6 |
| Cecum/ascending colon/hepatic flexure | 1.21 (1.05–1.40) | 0.007 | 3 | 49.3 |
| Transverse | 1.05 (0.94–1.18) | 0.397 | 2 | 0 |
| Descending | 1.08 (0.64–1.85) | 0.769 | 2 | 83.7 |
| Sigmoid | 1.02 (0.94–1.10) | 0.635 | 3 | 0 |
| RC | 0.94 (0.86–1.03) | 0.184 | 16 | 56.7 |
CC, colon cancer; RC, rectal cancer; RR, relative risk; CI, confidential interval.