Preworking, postworking and absolute change from preworking to postworking of lung function parameters in three occupational groups*
| Occupational groups | Preworking | Postworking | P values† | Mean (SD) of changes | β (95% CI)‡ | P values‡ |
| Mean (SD) | Mean (SD) | |||||
| Parameters | FVC (% predicted) | ΔFVC (% predicted) | ||||
| Conventional asphalt workers | 96.0 (11.8) | 95.7 (11.3) | 0.45 | −0.3 (4.5) | 0.6 (−0.7 to 1.9) | 0.38 |
| CRM asphalt workers | 98.2 (9.8) | 96.4 (9.9) | 0.06 | −1.2 (4.4) | −0.4 (−2.2 to 1.3) | 0.64 |
| Controls | 92.9 (11.1) | 92.0 (11.6) | 0.08 | −0.9 (4.9) | Ref | Ref |