Exposure-response estimates of silica and mortality from lung disease other than cancer by Poisson regression restricting observation to cumulative exposure <10 mg/m3.y (lung disease other than cancer, excluding pneumonia, n=56, person–years=64113)
| Model* | ai Estimate | Change in (−2lnl) | RR at 1.0 mg/m3.y† | RR at mean exposure‡ | RR at maximum exposure |
|---|---|---|---|---|---|
| *External adjusted models; stratifying on smoking (yes, no, unknown), ethnicity (Hispanics v other) and time since first observed (three levels) with external adjustment for age and calendar time using offset person-years×United States rate. Cumulative exposures were unlagged and classified in 50 levels together with unexposed level, a1 and a2 are estimated parameters in two parameter models; †Estimate for cumulative exposure of 1.0 mg/m3.y; ‡Evaluated at mean (5.79 mg/m3.y) and maximum (31.8 mg/m3.y) cumulative exposures of cases with lung disease other than cancer in full study population. | |||||
| Log linear | 0.1814 | 14.98 | 1.20 | 2.86 | 321.2 |
| Log square root | 0.6466 | 15.87 | 1.91 | 4.74 | 38.4 |
| Log quadratic: | |||||
| a1 | 0.4508 | 17.72 | 1.52 | 5.03 | 0.0 |
| a2 | −0.0297 | ||||
| Power | 0.7942 | 16.36 | 1.73 | 4.58 | 16.0 |
| Linear relative rate | 0.5469 | 16.49 | 1.55 | 4.17 | 18.4 |
| Shape: | |||||
| a1 | 0.4539 | 16.52 | 1.45 | 4.01 | 19.9 |
| a2 | 1.077 | ||||