Table 5. Positivity rate (PR), number of screen detected cancers and advanced adenomas, number of colonoscopies, detection rate (DR) of cancers and advanced adenomas (per 1000 screened subjects) and number needed to scope (NTS)a to find a cancer or a significant neoplasiab by screening strategy.
| Strategy | PR% | Number (difference %) | DR (‰) | NTSa | |||||
|---|---|---|---|---|---|---|---|---|---|
| Positive samples | Cutoff (ng ml−1) | Cancer | Advanced adenomas | Colonoscopies | Cancer | Advanced adenomas | Cancer | Significant neoplasiab | |
| At least one | ⩾80 | 8.0 | 69 (+21.1) | 465 (+44.4) | 1465 (+77.2) | 3.4 | 22.6 | 21.2 | 2.7 |
| At least one | ⩾100 | 6.7 | 69 (+21.1) | 406 (+26.1) | 1221 (+47.6) | 3.4 | 19.7 | 17.7 | 2.6 |
| At least one | ⩾120 | 5.9 | 67 (+17.5) | 380 (+18.0) | 1082 (+30.8) | 3.3 | 18.5 | 16.2 | 2.4 |
| One | ⩾80 | 5.5 | 59 (+3.5) | 368 (+14.3) | 1001 (+21.0) | 2.9 | 17.9 | 17.0 | 2.3 |
| Onec (reference) | ⩾100c | 4.5 | 57 | 322 | 827 | 2.8 | 15.6 | 14.5 | 2.2 |
| One | ⩾120 | 4.0 | 56 (−1.8) | 301 (−6.5) | 737 (−10.9) | 2.7 | 14.6 | 13.2 | 2.1 |
| Both | ⩾80 | 2.8 | 47 (−17.5) | 254 (−21.1) | 515 (−37.7) | 2.3 | 12.3 | 11.0 | 1.7 |
| Both | ⩾100 | 2.3 | 44 (−22.8) | 220 (−31.7) | 423 (−48.9) | 2.1 | 10.7 | 9.6 | 1.6 |
| Both | ⩾120 | 2.0 | 44 (−22.8) | 206 (−36.0) | 380 (−54.1) | 2.1 | 10.0 | 8.6 | 1.5 |
Differences (%) of number of cancers, advanced adenomas and colonoscopies with reference strategy are given in brackets.
a
NTS: number of FOBT+ colonoscopies needed to find a cancer or a significant neoplasia.
b
Significant neoplasia: cancer+advanced adenomas (any adenoma larger than 9 mm, and/or with a villous histological component higher than 20%, and/or with severe dysplasia).
c
Reference strategy: 1-day and cutoff ⩾100 ng ml−1.