Increase in dyspnoea 1, 2, or 3–4 grades by independent variables sex, age, and pack-yrs in a multinominal logistic regression model
| Δ1 increase | Δ2 increase | Δ3–4 increase | |
| Compared to no increase in dyspnoea | |||
| Sex | |||
| Females (compared to males) | 1.6 (1.2–2.2) | 2.4 (1.7–3.4) | 1.8 (1.0–3.1) |
| Age in 1985 (compared to 15–29) yrs | |||
| 30–49 | 0.9 (0.6–1.2) | 0.8 (0.5–1.2) | 1.0 (0.5–2.0) |
| 50–70 | 1.4 (0.9–2.0) | 2.1 (1.5–3.0) | 2.4 (1.3–4.6) |
| Pack-yrs | |||
| Per 10 pack-yrs increase | 1.3 (1.1–1.4) | 1.1 (1.0–1.3) | 1.2 (1.0–1.5) |
Data are presented as odds ratio (95% confidence intervals)