Table 2

Uptake, positivity rate and diagnostic yield of the faecal immunochemical test (FIT) at years 1, 2 and 3 and over all 3 years

UptakePositivity rateColonic exam performed Diagnostic yield*
Invited Completed FIT test Tested positive Any exam§ ColonoscopyColorectal cancer Advanced adenomas**
Year nn(%)n(%)n(%)n(%)n(%)n(%)
 180095938(74.1)346††(5.8)320(92.5)317(99.1)8(2.5)78(24.4)
 254795329(97.3)236(4.4)216(91.5)212(98.1)7(3.2)37(17.1)
 351795022(97.0)204(4.1)189(92.6)184(97.4)2(1.1)36(19.0)
 Cumulative80095938(74.1)786‡‡(13.2)725(92.2)713(98.3)17(2.3)151(20.8)
Routine year 3 colonic exam 45004420(98.2)12(0.3)295(6.6)
Entire study findings 52255133(98.2)29(0.6)446(8.5)
  • *Diagnostic yield in participants who underwent colonic examination.

  • †Participants who gave consent, returned an analysable FIT at year 1 and did not subsequently withdraw from the study.

  • ‡Percentages calculated using the number of participants who completed FIT as the denominator. In the pilot study, a threshold of 20 µg haemoglobin (Hb)/g faeces was used to denote test positivity. The positivity threshold used in the rest of the study was 40 µg Hb/g faeces.

  • §Participants who underwent colonoscopy or CT colonography. Percentages calculated using the number of FIT positive participants as the denominator.

  • ¶Participants who had a colonoscopy. Percentages calculated using the number of participants who underwent colonic examination as the denominator.

  • **Advanced adenomas were defined as adenomas ≥10 mm, with villous or tubulovillous histology, or high-grade dysplasia.

  • ††Three participants tested positive at year 1 during the pilot study based on a threshold of 20 µg Hb/g. They are included as FIT positive in this table even though their faecal haemoglobin levels were lower than the 40 µg Hb/g threshold used in the rest of the study.

  • ‡‡Participants who were FIT positive with any FIT, regardless of whether they had completed all FITs that they were offered.