Results obtained from the respiratory questionnaire
| Wheezing | |
| Yes | 51 (6.8) |
| No | 685 (91.3) |
| Does not know | 14 (1.9) |
| Sputum | |
| Yes | 76 (10.1) |
| No | 658 (87.7) |
| Does not know | 16 (2.1) |
| Cough | |
| Yes | 94 (12.5) |
| No | 640 (85.3) |
| Does not know | 16 (2.1) |
| Asthma | |
| Yes | 59 (7.9) |
| Confirmed | 54 (7.2) |
| No | 668 (89.1) |
| Does not know | 23 (3.1) |
| Dyspnoea (grade) | |
| Never (0) | 374 (49.9) |
| For intense effort (1) | 285 (38) |
| For moderate activities (2) | 74 (9.9) |
| For life activities (3) | 10 (1.3) |
| At rest (4) | 2 (0.3) |
| Does not know | 5 (0.7) |
| Smoking status | |
| Never | 454 (60.5) |
| Former | 233 (31.1) |
| Current | 63 (8.4) |
Data are presented as n (%).