Table 4 Odds ratio for lung cancer associated with occupational exposure to wood dust, stratified by smoking status, and test for interaction
Never-low smokers | Medium-heavy smokers | p-value | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Controls | Cases | OR* | 95% CI | Controls | Cases | OR* | 95% CI | (interaction) | |||
Study I | Population Controls | Population Controls | |||||||||
No exposure | 162 | 56 | 1.0 | (ref) | 227 | 574 | 1.0 | (ref) | |||
Any level of exposure | 48 | 19 | 0.7 | 0.3 | 1.4 | 96 | 208 | 0.7 | 0.5 | 1.0 | 0.714 |
Non-substantial level | 31 | 15 | 0.4 | 0.1 | 1.2 | 44 | 106 | 0.8 | 0.5 | 1.2 | 0.310 |
Substantial level | 17 | 4 | 1.0 | 0.4 | 2.8 | 52 | 102 | 0.6 | 0.4 | 1.0 | 0.110 |
Study I | Cancer controls | Cancer controls | |||||||||
No exposure | 411 | 56 | 1.0 | (ref) | 661 | 574 | 1.0 | (ref) | |||
Any level of exposure | 83 | 19 | 0.9 | 0.4 | 1.7 | 194 | 208 | 1.2 | 0.9 | 1.5 | 0.508 |
Non-substantial level | 50 | 7 | 0.5 | 0.2 | 1.3 | 111 | 106 | 1.0 | 0.8 | 1.4 | 0.790 |
Substantial level | 33 | 12 | 1.6 | 0.7 | 3.9 | 83 | 102 | 1.3 | 0.9 | 1.9 | 0.235 |
Study II | Population Controls | Population Controls | |||||||||
No exposure | 269 | 40 | 1.0 | (ref) | 371 | 461 | 1.0 | (ref) | |||
Any level of exposure | 87 | 10 | 0.8 | 0.3 | 1.8 | 167 | 225 | 1.2 | 0.9 | 1.6 | 0.196 |
Non-substantial level | 70 | 5 | 0.5 | 0.2 | 1.3 | 131 | 162 | 1.1 | 0.8 | 1.5 | 0.078 |
Substantial level | 17 | 5 | 2.4 | 0.7 | 7.9 | 36 | 63 | 1.6 | 1.0 | 1.5 | 0.805 |