Baseline patient and sigmoidoscopy characteristics
| Characteristic | No (%) |
|---|---|
| *Colorectal cancer (CRC) in one first degree relative diagnosed at age 55 years or older. | |
| †Size ⩾1 cm, villous histology, and/or severe dysplasia. | |
| Age (y) | |
| 50–59 | 26 141 (46.9) |
| 60–69 | 20 452 (36.7) |
| 70–79 | 8381 (15.0) |
| 80+ | 817 (1.5) |
| Sex | |
| Male | 29 537 (52.9) |
| Female | 26 248 (47.1) |
| Endoscopist specialty | |
| Gastroenterologist | 15 199 (27.2) |
| Non-gastroenterologist MD | 29 036 (52.0) |
| Nurse | 8111 (14.5) |
| Unknown | 3445 (6.2) |
| Family history of CRC* | |
| No | 51 486 (92.3) |
| Yes | 4305 (7.7) |
| History of prior sigmoidoscopy | |
| No | 41 836 (76.1) |
| Yes | 13 121 (23.9) |
| Depth of sigmoidoscope insertion (cm) | |
| <30 | 1733 (3.1) |
| 30–39 | 3897 (7.0) |
| 40–49 | 6061 (10.9) |
| 50–59 | 8522 (15.3) |
| 60+ | 35 578 (63.8) |
| Most advanced finding | |
| No polyps | 45 863 (82.2) |
| Non-adenomatous polyp | 5035 (9.0) |
| Non-advanced adenoma | 3970 (7.1) |
| Advanced adenoma† | 923 (1.7) |
| Examination limited by | |
| Spasm/pain | 9967 (17.9) |
| Stool | 7959 (14.3) |
| Angulation | 8030 (14.4) |