Variable | Coefficient (β) | 95% CIs | p Value |
---|---|---|---|
Study sample size | |||
n>100 | Reference | ||
n≤100 | 0.12 | 0.22 | |
Time period of the study | |||
<2000 | Reference | ||
≤2000 and <2008 | −0.7 | (−1.8 to 0.5) | 0.47 |
≥2008 | −0.2 | (−1.2 to 0.8) | 0.76 |
Patient enrolment per year | |||
N≤29 | Reference | ||
N>29 | −0.7 | (−1.5 to 0.02) | 0.05 |
Study design | |||
Single-centre study | Reference | ||
Multi-centre study | 0.3 | (−0.4 to 1.1) | 0.45 |
Patient mean age (years) | |||
<67 | Reference | ||
≥67 | −0.6 | (−1.3 to 0.006) | 0.05 |
Ratio of sessile polyps to peduncolated polyps (%) | |||
>50 | Reference | ||
≤50 | −0.6 | (−1.5 to 0.2) | 0.17 |
Ratio of non-polypoid polyps (%) | |||
>40 | Reference | ||
≤40 | 0.2 | (−1.4 to 1.2) | 0.73 |
Positive meta-regression coefficients express an increased rate compared with the reference group. τ2 (estimate of residual amount of heterogeneity): 0.5254 (SE=0.2159).