Relationship between variables and high and low ADR
| Variables | Subgroups | Low ADR (<20%) n=147 | High ADR (≥20%) n=305 | P value (95% CI) |
| Mean age (SD) years | 58.7 (15.8) | 58.6 (15.6) | 0.941 | |
| Mean CWT (SD) min | 8.21 (4.08) | 9.63 (4.4) | 0.001 | |
| Endoscopist specialty | Trainee | 110 | 86 | 0.0001 |
| Gastroenterologist | 17 | 341 | ||
| Surgeon | 155 | 73 | ||
| Polypectomy | No polypectomy | 238 | 413 | 0.044 |
| Cold biopsy | 22 | 63 | ||
| Cold snare | 22 | 25 | ||
| Tolerance | Poor | 8 | 13 | 0.044 |
| Acceptable | 5 | 29 | ||
| Good | 232 | 423 | ||
| Biopsies | No biopsy | 80 | 221 | 0.0001 |
| Biopsies | 202 | 280 | ||
| Indications | Change bowel habit | 125 | 242 | 0.436 |
| Anaemia | 42 | 91 | ||
| Melaena/PR bleed | 31 | 55 | ||
| Polyp surveillance | 37 | 38 | ||
| Abdominal pain | 12 | 25 | ||
| Colitis surveillance | 13 | 22 | ||
| Abnormal radiology | 7 | 11 | ||
| Diarrhoea | 6 | 8 | ||
| Weight loss | 3 | 1 | ||
| Family Hx of colorectal cancer | 1 | 2 | ||
| Constipation | 1 | 1 | ||
| Incontinence | 0 | 1 | ||
| Missing data | 4 | 4 |
ADR, adenoma detection rate; CWT, colonoscopy withdrawal time; Hx, history; PR, per rectal.