Joint-years | Cases | Controls | RR of respiratory tract cancer (95% CI) |
---|---|---|---|
*Adjusted for age, sex, ethnicity and family history and pack-years of tobacco use. | |||
None | 117 | 285 | 1.00 |
1st tertile | 5 | 19 | 0.40 (0.12–1.31) |
2nd tertile | 9 | 15 | 0.95 (0.38–2.40) |
3rd tertile | 19 | 5 | 3.47 (1.13–10.7) |