Table 3

Incidence of advanced CRCs or mortality from CRC in the exposed and unexposed groups and their crude and adjusted relative rates of the effectiveness of FIT screening between the two groups

Unexposed group
(N=2 349 846)
Exposed group
(N=3 067 853)
Relative rate (95% CI), exposed versus unexposed
Case (n)Rate
(per 105)
Case (n)Rate
(per 105)
CrudeAge-adjusted and gender-adjustedaRR1
(adjusting for screening rate)*
aRR2
(full adjustment)‡
Incidence of advanced cancer†
 Overall23 68975.7638148.40.64 (0.62 to 0.66)0.52 (0.50 to 0.53)0.71 (0.68 to 0.75)0.66 (0.63 to 0.70)
 Proximal612719.6207015.70.80 (0.76 to 0.84)0.62 (0.59 to 0.65)0.92 (0.84 to 1.00)0.84 (0.77 to 0.92)
 Distal17 40455.6426732.30.58 (0.56 to 0.60)0.48 (0.46 to 0.50)0.65 (0.62 to 0.69)0.61 (0.58 to 0.64)
Mortality
 Overall15 55041.3307720.30.49 (0.47 to 0.51)0.44 (0.43 to 0.46)0.65 (0.62 to 0.69)0.60 (0.57 to 0.64)
 Proximal400410.69886.50.61 (0.57 to 0.66)0.54 (0.50 to 0.58)0.79 (0.72 to 0.87)0.72 (0.66 to 0.80)
 Distal11 44030.4207613.70.45 (0.43 to 0.47)0.41 (0.39 to 0.43)0.61 (0.57 to 0.64)0.56 (0.53 to 0.59)
  • Person-years were 13 196 865 in the exposed group and 31 294 921 in the unexposed group for calculating incidence of advanced cancer; person-years was 15 179 449 in the exposed group and 37 658 371 in the unexposed group for calculating CRC mortality.

  • *Adjusting for age and gender with self-selection bias. Embedded Image, where D, E, Embedded Image, I and Embedded Image represent CRC death, exposed, not exposed, invited and not invited to FIT screening, respectively.

  • †Advanced cancer refers to CRC stage II or higher.

  • ‡Adjusting for age, gender, attendance, referral, selection of diagnostic examination modality and completeness for colonoscopy, Embedded Image with numerator further expanded and written as follows Embedded Imagewhere Embedded Image, Embedded Image, Embedded Image, Embedded Image, Embedded Image denote cecal intubation rate, the proportion of selecting colonoscopy, referral rate to diagnosticexamination, positive rate and screening rate

  • aRR1, first adjusted relative rate; aRR2, second adjusted relative rate; CRC, colorectal cancer; FIT, faecal immunochemical test.