Table 2

Relative risk to develop FOBT iCRC per screening round, in years since last negative test, and cut-off

Subgroup variableStudies, nRelative risk (95% CI)Study references
Screening round
 115Reference 6 27 28 31 32 36–39 42 44–46 51 52
 250.93 (0.85 to 1.02) 6 36 45 46 52
 340.76 (0.66 to 0.88) 6 36 45 52
 410.77 (0.54 to 1.10) 36
Time in years since last negative test
 18Reference 2 27 28 38 42 45 50
 261.25 (1.05 to 1.57) 2 27 28 38 42 50
 321.19 (0.76 to 1.87) 27 42
Cut-off*
 Per 10 µg Hb/g faeces increase171.00 (0.89 to 1.13) 28–30 32 33 35 36 38 39 41 44 50 52
  • *Based on 13 studies that used a single fixed cut-off.

  • FOBT, faecal occult blood test; Hb, haemoglobin; iCRC, interval colorectal cancer.