Characteristics of new starters who were 18 years or older at the first sets of tests
| Group | |||||
|---|---|---|---|---|---|
| Operation | Maintenance | Electricity | Other | Total | |
| *Proportions of non-smokers, ex-smokers, and current smokers in each group. | |||||
| †Distributions of current smokers by pack-years and their proportions. | |||||
| ‡The numbers of observations for FEV1, FVC, and FEV1/FVC are 613; for FEF25–75% 202. | |||||
| Subjects (no.) | 426 | 96 | 31 | 60 | 613 |
| Age (years), mean (SD) | 27.1 (8.8) | 29.4 (11.5) | 26.6 (8.8) | 29.5 (9.9) | 27.7 (9.4) |
| Min–max (years) | 18.0–60.1 | 18.2–60.1 | 18.6–48.4 | 18.5–58.2 | 18.0–60.1 |
| Height (cm), mean (SD) | 173.7 (7.2) | 173.3 (7.9) | 175.7 (8.3) | 173.6 (7.8) | 173.7 (7.4) |
| Min–max (cm) | 156–199 | 153–190 | 162–196 | 158–193 | 153–199 |
| Non-smokers, no. (%)* | 98 (23.0) | 23 (24.0) | 5 (16.1) | 16 (26.6) | 142 (23.2) |
| Ex-smokers, no. (%)* | 30 (7.0) | 12 (12.5) | 6 (19.4) | 1 (1.7) | 49 (8.0) |
| Current smokers, no. (%)* | 298 (70.0) | 61 (63.5) | 20 (64.5) | 43 (71.7) | 422 (68.8) |
| <10 pack-years, no. (%)† | 262 (87.9) | 49 (80.3) | 17 (85.0) | 36 (83.7) | 364 (86.3) |
| 10–20 pack-years, no. (%)† | 26 (8.7) | 7 (11.5) | 2 (10.0) | 4 (9.3) | 39 (9.2) |
| ≥20 pack-years, no. (%)† | 10 (3.4) | 5 (8.2) | 1 (5.0) | 3 (7.0) | 19 (4.5) |
| Lung function, mean (SD) | |||||
| FEV1 (l)‡ | 3.70 (0.70) | 3.66 (0.66) | 3.82 (0.73) | 3.65 (0.76) | 3.69 (0.70) |
| FVC (l)‡ | 4.47 (0.80) | 4.40 (0.71) | 4.54 (0.75) | 4.37 (0.90) | 4.45 (0.79) |
| FEV1/FVC (%)‡ | 83.82 (8.14) | 83.16 (8.02) | 83.85 (5.53) | 83.63 (6.97) | 83.00 (7.89) |
| FEF25–75% (l/s)‡ | 3.88 (1.30) | 3.64 (1.29) | 4.07 (1.57) | 4.23 (1.14) | 3.87 (1.29) |