Distribution of subjects according to selected socio-demographic characteristics
| Variable | Categories | Study I | Study II | ||
| Controls (N=533) | Cases (N=857) | Controls (N=894) | Cases (N=736) | ||
| Age (years) | ≤55 | 28.0% | 27.4% | 11.9% | 13.6% |
| 56–65 | 45.2% | 50.8% | 28.6% | 32.9% | |
| 66–75 | 26.8% | 21.8% | 59.5% | 53.5% | |
| Ethnicity | French Canadian | 64.2% | 69.1% | 64.4% | 77.4% |
| English Canadian | 14.1% | 13.5% | 6.4% | 4.6% | |
| Other | 21.8% | 17.4% | 29.2% | 18.0% | |
| Schooling (years) | <7 | 20.3% | 30.3% | 24.9% | 28.7% |
| 7–12 | 56.1% | 57.1% | 47.9% | 54.6% | |
| 13+ | 23.6% | 12.6% | 27.2% | 16.7% | |
| Median family income* (in Can$) | 26 627 | 22 386 | 35 187 | 32 961 | |
| Smoking status | Never | 19.7% | 1.5% | 17.7% | 2.4% |
| Quit 2–5 years ago | 8.8% | 7.6% | 3.0% | 4.3% | |
| Quit 6–10 years ago | 7.9% | 6.0% | 6.6% | 5.8% | |
| Quit >10 years ago | 16.7% | 5.0% | 43.7% | 19.8% | |
| Current† | 46.9% | 79.9% | 29.0% | 67.5% | |
| Mean pack-years‡ | 49.9 | 74.3 | 50.3 | 78.5 | |
| Respondent | Self | 87.4% | 70.6% | 90.3% | 60.2% |
| Proxy | 12.6% | 29.4% | 9.7% | 39.8% | |