Table 3.

Results of per-protocol analysis reported in the original NordICC trial report by Bretthauer et al. [1] and the re-analysis by Shi et al. [2]

Publication, year (reference)	Analysis	Relative risk (95% CI)
		CRC incidence	CRC mortality
Bretthauer et al. 2022 [1]	Intention-to-screen	0.82 (0.70–0.93)	0.90 (0.64–1.16)
	Adjusted per-protocol, main analysisa	0.69 (0.55–0.83)	0.50 (0.27–0.77)
	Adjusted per-protocol, sensitivity analysisb	0.66 (0.46–0.86)	0.72 (0.00-3.70)
Shi et al. 2025 [2]	Adjusted per-protocol, instrumental variable analysisc	0.59 (0.30–0.98) 0.65 (0.48–0.87)	0.71 (0.31–2.89) to 0.79 (0.24–1.42)

^aAdjusted for baseline covariates: age at randomization, sex, country, duration of follow-up

^bAdjusted by the method proposed by Cuzick et al. [19]

^cInstrumental variable analyses with different assumptions: additive homogeneity, multiplicative homogeneity, and monotonicity