Multivariate hazards RRs (95% CIs) of prognostic factors for the occurrence of sickness absence due to respiratory disorders
| Cause of sickness absence and factor | Subjects | RR | (95% CI) | p Value |
| Asthma: | ||||
| Age (y): | ||||
| ⩽40 | 125 | 1.00 | ||
| >40 | 126 | 0.65 | (0.35 to 1.22) | 0.18 |
| FVC: | ||||
| >80% Of reference FVC | 228 | 1.00 | ||
| ⩽80% Of reference FVC | 10 | 4.03 | (1.41 to 11.54) | 0.009 |
| Asthma complaints before study: | ||||
| No | 219 | 1.00 | ||
| Yes | 32 | 3.96 | (1.99 to 7.90) | 0.000 |
| Chronic obstructive pulmonary disease: | ||||
| Age (y): | ||||
| ⩽40 | 125 | 1.00 | ||
| >40 | 126 | 0.78 | (0.49 to 1.25) | 0.31 |
| Office workers | 29 | 1.00 | ||
| v Metal workers | 125 | 2.77 | (0.99 to 7.75) | 0.05 |
| v Welders | 97 | 2.73 | (0.95 to 7.79) | 0.06 |
| Chronic non-specific lung disease: | ||||
| Age (y): | ||||
| ⩽40 | 125 | 1.00 | ||
| >40 | 126 | 0.69 | (0.44 to 1.08) | 0.1 |
| FVC: | ||||
| >80% Of reference FVC | 228 | 1.00 | ||
| ⩽80% Of reference FVC | 10 | 2.49 | (1.07 to 5.79) | 0.034 |
| Office workers | 29 | 1.00 | ||
| v Metal workers | 125 | 2.91 | (1.04 to 8.13) | 0.04 |
| v Welders | 97 | 3.52 | (1.24 to 9.97) | 0.018 |