UICC stages 1 or 2 | No colonoscopy | 160 (94.1%) | 1.00 Reference |
Colonoscopy | Any | 10 (5.9%) | 0.20 (0.10 to 0.40) |
| 1–4 years ago | 4 (2.4%) | 0.14 (0.05 to 0.38) |
| 5+ years ago | 6 (3.5%) | 0.30 (0.12 to 0.72) |
UICC stages 3 or 4 | No colonoscopy | 155 (90.6%) | 1.00 Reference |
Colonoscopy | Any | 16 (9.4%) | 0.28 (0.16 to 0.50) |
| 1–4 years ago | 9 (5.3%) | 0.25 (0.12 to 0.52) |
| 5+ years ago | 7 (4.1%) | 0.33 (0.14 to 0.75) |
Proximal colon cancer | No colonoscopy | 125 (89.3%) | 1.00 Reference |
Colonoscopy | Any | 15 (10.7%) | 0.40 (0.21 to 0.72) |
| 1–4 years ago | 9 (6.4%) | 0.41 (0.20 to 0.87) |
| 5+ years ago | 6 (4.3%) | 0.38 (0.16 to 0.92) |
Caecum and ascending colon | No colonoscopy | 66 (85.7%) | 1.00 Reference |
Any colonoscopy | 11 (14.3%) | 0.50 (0.25 to 1.00) |
Other proximal colon cancer | No colonoscopy | 60 (93.8%) | 1.00 Reference |
Any colonoscopy | 4 (6.3%) | 0.24 (0.08 to 0.68) |
Distal cancer (sigmoid or rectum) | No colonoscopy | 208 (94.1%) | 1.00 Reference |
Colonoscopy | Any | 13 (5.9%) | 0.17 (0.09 to 0.32) |
| 1–4 years ago | 6 (2.7%) | 0.12 (0.05 to 0.30) |
| 5+ years ago | 7 (3.2%) | 0.25 (0.11 to 0.57) |
Sigmoid | No colonoscopy | 64 (94.1%) | 1.00 Reference |
Any colonoscopy | 4 (5.9%) | 0.13 (0.04 to 0.43) |
Rectum | No colonoscopy | 144 (94.1%) | 1.00 Reference |
Any colonoscopy | 9 (5.9%) | 0.19 (0.09 to 0.39) |