Table 2

Interrupted time series by anatomic site and sex in the target population of FIT-based screening (50–69 years)

	Parameter	Overall RR (95% CI)	Proximal RR (95% CI)	Distal RR (95% CI)	Rectal RR (95% CI)
Male	Pre-FIT slope	0.99 (0.97 to 1.00)	1.05 (1.01 to 1.08)	0.96 (0.93 to 0.99)	0.96 (0.94 to 0.99)
	Level change	1.25 (1.14 to 1.38)	1.07 (0.93 to 1.24)	1.50 (1.29 to 1.74)	1.24 (1.09 to 1.41)
	Slope change	0.96 (0.94 to 0.98)	0.94 (0.91 to 0.97)	0.96 (0.92 to 0.99)	0.97 (0.94 to 0.99)
	Post-FIT slope	0.94 (0.94 to 0.95)	0.99 (0.97 to 1.00)	0.91 (0.90 to 0.93)	0.93 (0.92 to 0.94)
Female	Pre-FIT slope	1.01 (0.99 to 1.03)	1.03 (1.00 to 1.07)	1.00 (0.97 to 1.04)	1.00 (0.97 to 1.04)
	Level change	1.27 (1.14 to 1.41)	1.35 (1.14 to 1.59)	1.28 (1.07 to 1.52)	1.19 (1.01 to 1.39)
	Slope change	0.94 (0.92 to 0.96)	0.95 (0.91 to 0.98)	0.92 (0.89 to 0.96)	0.93 (0.90 to 0.96)
	Post-FIT slope	0.95 (0.94 to 0.96)	0.97 (0.96 to 0.99)	0.93 (0.92 to 0.95)	0.93 (0.92 to 0.94)

Statistically significant estimates at the alpha=0.05 level are shown in bold.
‘Pre-FIT slope’ represents the trend before the screening implementation. ‘Level change’ indicates the level change in the mean outcome that occurs in the period immediately following the screening implementation. ‘Slope change’ indicates the difference between prescreening and postscreening implementation slopes of the mean outcome. ‘Post-FIT slope’ represents the postscreening implementation trend.
FIT, faecal immunochemical test; RR, rate ratio.