| 8–15 years | 10–20 years | 8–15 years | 10–20 years | |
| IBD–CRC interval (%) | IBD–CRC interval (%) | OoS–CRC interval (%) | OoS–CRC interval (%) | |
| All cases | ||||
| CRC before SPoS | 33 (22) | 41 (28) | 25 (17) | 33 (22) |
| CRC after SPoS | 116 (78) | 108 (72) | 124 (83) | 116 (78) |
| Total | 149 (100) | 149 (100) | 149 (100) | 149 (100) |
| Ulcerative colitis | ||||
| CRC before SPoS | 19 (21) | 25 (28) | 14 (16) | 19 (21) |
| CRC after SPoS | 70 (79) | 64 (72) | 75 (84) | 70 (79) |
| Total | 89 (100) | 89 (100) | 89 (100) | 89 (100) |
| Crohn’s disease | ||||
| CRC before SPoS | 13 (22) | 15 (25) | 10 (17) | 13 (22) |
| CRC after SPoS | 46 (78) | 44 (75) | 49 (83) | 46 (78) |
| Total | 59 (100) | 59 (100) | 59 (100) | 59 (100) |
All numbers for 8–15 IBD–CRC interval and 10–20 OoS–CRC interval are the same which is purely coincidental.
CRC, colorectal cancer; IBD, inflammatory bowel disease; OoS, onset of symptoms; SPoS, starting point of surveillance.