Table 1.
Subject characteristics | Cases (n=307) | Controls (n=1016) | Crude OR | 95% CI | p Value | Multivariate analysis OR | 95% CI |
Mean (SEM) age (y) | 32.7 (0.85) | 33.6 (0.38) | 0.32 | ||||
Sex | |||||||
Female | 48.9% | 45.8% | 0.34 | ||||
Male | 51.1% | 54.2% | |||||
Smoking | |||||||
Never smoker | 54.4% | 52.6% | 1.00 | (referent) | 1.00 | (referent) | |
Current smoker | 3.3% | 32.1% | 0.10 | 0.05–0.19 | 0.10 | 0.05–0.19 | |
Ex-smoker | 42.3% | 15.3% | 2.71 | 2.03–3.64 | <0.0001 | 3.29 | 2.38–4.56 |
(n=307) | (n=896) | ||||||
Appendicectomy | |||||||
No | 93.2% | 76.9% | 1.00 | (referent) | 1.00 | (referent) | |
Yes | 6.8% | 23.1% | 0.23 | 0.15–0.39 | <0.0001 | 0.23 | 0.14–0.38 |
(n=307) | (n=892) | ||||||
Age at appendicectomy | |||||||
None | 93.2% | 77.1% | 1.00 | (referent) | 1.00 | (referent) | |
≤20 y | 3.3% | 15.3% | 0.17 | 0.09–0.34 | 0.16 | 0.08–0.32 | |
>20 y | 3.5% | 7.6% | 0.39 | 0.20–0.75 | <0.0001 | 0.41 | 0.20–0.83 |