Occupational asthma group: causes and method of independent diagnosis
| Causes | Occupational asthma group (%) |
| High molecular weight agents | |
| Total | 21 |
| Latex | 7 |
| Flour | 5 |
| Enzymes | 6 |
| Other | 3 |
| Low molecular weight agents | |
| Total | 79 |
| Cleaning agents | 17 |
| Isocyanates | 18 |
| Solder flux flume | 8 |
| Metal working fluid | 7 |
| Metals | 5 |
| Adhesives | 7 |
| Other | 17 |
| Methods of independent diagnosis | |
| Challenge positive | 59 |
| Asthma + IgE +history alone | 26 |
| NSBR×4 alone | 15 |
NSBR, non-specific bronchial reactivity; a fourfold change was needed between work and rest periods for inclusion.