Table 9. Distribution of smoking habits and UBC risk in the present case-control study.
| Smoking Habit (n Ca/n Co) | Cases | Controls | OR (95% CI) | OR adj (95% CI adj) |
| Non-smokers (321/752) | 21% | 44% | (reference) | (reference) |
| Former smokers (742/656) | 50% | 38% | 2.65 (2.24–3.31) | 2.12 (1.78–2.53) |
| Current smokers (431/315) | 29% | 18% | 3.21 (2.64–3.90) | 3.28 (2.67–4.03) |
| Ever smokers (1173/971) | 79% | 56% | 2.83 (2.42–3.31) | 2.47 (2.10–2.90) |
For each of the smoker subgroups containing nCa cases and nCo controls, the odds ratios (OR) and their corresponding 95% confidence intervals (95% CI) were computed, both not adjusted and adjusted for age and gender. The latter odds ratios are abbreviated by OR adj.