Diagnostic accuracy of FIT for CRC at different cut-offs
Cut-off (µg/g) | Positivity (%) | NNS | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | TP | FN | FP | TN |
2 | 37.2 | 11.5 | 97.0 (94.5 to 98.5) | 64.9 (63.9 to 65.8) | 8.7 (7.8 to 9.7) | 99.8 (99.7 to 99.9) | 319 | 10 | 3336 | 6157 |
10 | 19.0 | 6.2 | 90.9 (87.2 to 93.8) | 83.5 (82.8 to 84.3) | 16.1 (14.4 to 17.8) | 99.6 (99.5 to 99.7) | 299 | 30 | 1563 | 7930 |
150 | 7.6 | 3.2 | 70.8 (65.6 to 75.7) | 94.6 (94.1 to 95.0) | 31.1 (27.8 to 34.6) | 98.9 (98.7 to 99.1) | 233 | 96 | 516 | 8977 |
<2 | 62.8 | 616.7 | 3 (1.5 to 5.5) | 35.1 (34.2 to 36.1) | 0.2 (0.1 to 0.3) | 91.3 (90.3 to 92.2) | 10 | 319 | 6157 | 3336 |
95% CIs within brackets.
CRC, colorectal cancer; FIT, faecal immunochemical test; FN, false negatives; FP, false positives; NNS, number needed to scope; NPV, negative predictive value; PPV, positive predictive value; TN, true negatives; TP, true positives.