Comparison 1. Dietary fibre (all study interventions) versus control.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Number of participants with at least one recurrent adenoma	5	3641	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.95, 1.13]
2 Number of participants with more than one adenoma	2	2542	Risk Ratio (M‐H, Fixed, 95% CI)	1.06 [0.94, 1.20]
3 Number of participants with at least one adenoma 1 cm or greater	4	3224	Risk Ratio (M‐H, Fixed, 95% CI)	0.99 [0.82, 1.20]
4 Number of participants diagnosed with colorectal cancer	2		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.1 One‐ year data	1	1905	Risk Ratio (M‐H, Fixed, 95% CI)	1.98 [0.36, 10.77]
4.2 Up to 4 years	2	2794	Risk Ratio (M‐H, Fixed, 95% CI)	2.70 [1.07, 6.85]