Association between a positive skin prick test to rat urine and new work related symptoms, with new work related chest symptoms following a positive skin prick test to rat urine
| Skin prick test | ||
|---|---|---|
| Yes | No | |
| Relative risk: 3.6 (95% CI 2.9 to 4.5). | ||
| Chest symptoms | ||
| Yes | 12 | 18 |
| No | 34 | 234 |









