Table 2 ‘Rectal bleeding’ before diagnosis in colorectal cancer patients, with added sensitivity figures for patients with positive Faecal occult blood test (FOBT) and/or Anaemia. Cohort study with 61,802 patients in primary care (2011–12)
N | Sensitivity (A) | PPV (A) | Sensitivity (B) | Sensitivity (C) | Sensitivity (D) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
All | Males | Females | All | 95% CI | All | 95% CI | Males | Females | All | 95% CI | All | 95% CI | All | 95% CI | |
Colorectal cancer | 94 | 35 | 59 | 17.0% | 10.8–25.9 | 4.0% | 2.5–6.4 | 2.0% | 5.1% | 39.4% | 30.1–49.5 | 47.9% | 38.1–57.9 | 57.5% | 47.4–67.0% |
A | 16 | 3 | 13 | ||||||||||||
B | 37 | 13 | 24 | ||||||||||||
Colon cancer | 65 | 22 | 43 | 12.3% | 6.4–22.5 | 2.0% | 1.0–4.0 | 0.7% | 2.8% | 32.3% | 22.2–44.4 | 41.5% | 30.4–53.7 | 55.4% | 43.3–66.8 |
A | 8 | 1 | 7 | ||||||||||||
B | 21 | 6 | 15 | ||||||||||||
Colon, proximal cancer | 18 | - | - | 16.7% | 5.8–39.2 | 22.2% | 9.0–45.2 | 38.9% | 20.3–61.4 | ||||||
A | 0 | ||||||||||||||
B | 3 | 1 | 2 | ||||||||||||
Colon, distal cancer | 26 | 23.1% | 11.0–42.1 | 1.5% | 0.7–3.3 | - | 2.4% | 46.2% | 28.8–64.5 | 57.7% | 39.0–74.5 | 69.2% | 50.0–83.5 | ||
A | 6 | 0 | 6 | ||||||||||||
B | 12 | 1 | 11 | ||||||||||||
Rectal cancer | 29 | 13 | 16 | 27.6% | 14.7–25.7 | 2.0% | 1.0–4.0 | 1.3% | 2.4% | 55.2% | 37.6–71.6 | 62.1% | 44.0–77.3 | 62.1% | 44.0–77.3 |
A | 8 | 2 | 6 | ||||||||||||
B | 16 | 7 | 9 | ||||||||||||
Colorectal cancer (A), specificity: | Specificity 99.4% (95% CI 99.3–99.4), based on 385 patients with 'Rectal bleeding' without cancer, and 60,777 patients with no 'Rectal bleeding' and no cancer | ||||||||||||||