Table 1

Comparison of the performance of triage tools in the detection of colorectal cancer and significant bowel disease in cohort of 388 patients in whom faecal immunochemical testing was performed

FAST score ≥4.5f-Hb ≥10 µg/gColon flag band 3f-Hb ≥10 µg/g and/or
ColonFlag band 3
CRC
 No of cases11111
 True positives89911
 True negatives303245277187
 False positives73132100190
 False negatives3220
 Sensitivity72.7 (39.0–94.0)81.8 (48.2–97.7)81.8 (48.2–97.7)100 (71.5–100)
 Specificity80.6 (76.2–84.5)64.9 (59.9–69.8)73.5 (68.7–77.9)49.6 (44.4–54.8)
 PPV9.9 (6.7–14.3)6.4 (4.8–8.5)8.3 (6.1–11.1)5.5 (4.9–6.0)
 NPV99.0 (97.5–99.6)99.2 (97.2–99.8)99.3 (97.6–99.8)100
CRC+HRA
 No of cases35353535
 True positives21251530
 True negatives293237259182
 False positives6011694171
 False negatives1410205
 Sensitivity60.0 (42.1–76.1)71.4 (53.7–85.4)42.9 (26.3–60.7)85.7 (69.7–95.2)
 Specificity83.0 (78.7–86.8)67.3 (62.2–72.2)73.4 (68.4–77.9)51.6 (46.2–56.9)
 PPV25.9 (19.70–33.3)17.9 (14.4–21.0)13.7 (9.5–19.5)14.9 (12.9–17.3)
 NPV95.4 (93.3–96.9)95.6 (93.3–97.6)92.8 (90.6–−94.6)97.3 (94.1–98.8)
CRC+HRA+IBD
 No of cases43434343
 True positives29331738
 True negatives293237253182
 False positives5210892163
 False negatives1410265
 Sensitivity67.4 (51.5–80.9)76.7 (61.4–88.2)39.5 (25.0–55.6)88.4 (74.9–96.1)
 Specificity84.9 (80.7–88.5)68.7 (63.5–73.6)73.3 (68.3–78.0)52.8 (47.3–58.1)
 PPV35.8 (28.7–43.6)23.4 (19.6–27.7)15.6 (10.9–21.8)18.9 (16.64–21.4)
 NPV95.4 (93.1–97.0)96.0 (93.2–97.6)69.6 (64.7–74.1)97.3 (94.1–98.8)
  • CRC, colorectal cancer; f-HB, faecal haemoglobin; HRA, high risk adenomas; IBD, inflammatory bowel disease; NPV, negative predictive value; PPV, positive predictive value.