Comparison 1. Surveillance versus non surveillance.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Cancer detection	3	7151	Odds Ratio (M‐H, Fixed, 95% CI)	0.58 [0.42, 0.80]
2 Death from colorectal cancer	4	530	Odds Ratio (M‐H, Fixed, 95% CI)	0.36 [0.19, 0.69]
3 Cancer Stage‐ Duke A	2	227	Odds Ratio (M‐H, Fixed, 95% CI)	3.69 [0.80, 17.12]
4 Cancer Stage‐ Duke B	2	227	Odds Ratio (M‐H, Fixed, 95% CI)	2.38 [0.73, 7.73]
5 Cancer stage‐ Duke C	2	227	Odds Ratio (M‐H, Fixed, 95% CI)	0.33 [0.11, 0.98]
6 Cancer stage‐ Duke D	1	186	Odds Ratio (M‐H, Fixed, 95% CI)	1.05 [0.25, 4.31]
7 Cancer stage‐ Duke A or B	2	227	Odds Ratio (M‐H, Fixed, 95% CI)	5.40 [1.51, 19.30]
8 Cancer stage‐ Duke C or D	2	227	Odds Ratio (M‐H, Random, 95% CI)	0.46 [0.08, 2.51]
9 Colectomy	1	186	Odds Ratio (M‐H, Fixed, 95% CI)	0.49 [0.27, 0.88]