Exposure specific mortality rates and mortality rate ratios from silicosis
| Adjusted† rate ratio | |||||
|---|---|---|---|---|---|
| Cumulative exposure to crystalline silica (mg/m3-y) | Person years (×100000) | Silicosis mortality rate (per 100000 py)* | Adjusted† silicosis mortality rate (per 100000 py) | RR | (95% CI) |
| *Each category includes 17 silicosis deaths (total 170). | |||||
| †Adjusted for age in four categories, calendar period in eight categories, study in six categories, using Poisson regression. | |||||
| n.a., not applicable. | |||||
| 0–0.99 | 3.637 | 4.7 | 4.7 | 1.00 | (referent) |
| 0.99–1.97 | 0.631 | 26.9 | 15.9 | 3.39 | (1.42 to 8.08) |
| 1.97–2.87 | 0.291 | 58.4 | 29.2 | 6.22 | (2.56 to 15.12) |
| 2.87–4.33 | 0.252 | 67.4 | 44.2 | 9.40 | (3.71 to 23.80) |
| 4.33–7.12 | 0.278 | 61.1 | 64.3 | 13.69 | (5.04 to 37.18) |
| 7.12–9.58 | 0.188 | 90.6 | 106.4 | 22.64 | (7.88 to 65.10) |
| 9.58–13.21 | 0.204 | 83.2 | 112.6 | 23.97 | (8.05 to 71.32) |
| 13.21–15.89 | 0.118 | 144.7 | 189.2 | 40.25 | (13.25 to 122.3) |
| 15.89–28.10 | 0.231 | 73.6 | 118.0 | 25.11 | (8.09 to 77.91) |
| >28.10 | 0.073 | 233.6 | 299.1 | 63.63 | (19.87 to 203.8) |
| Total | 5.903 | 28.8 | n.a. | n.a. | n.a. |