Model for asbestosis mortality as an underlying or contributing cause of death among workers in the South Carolina asbestos textile workers cohort*
| Term in model | Estimate | Standard error | Likelihood ratio test† | ||
|---|---|---|---|---|---|
| *Power model for asbestosis mortality rate is given by λ = λ0 × (E + α)β where λ0 = exp[β0 + β1(sex = female) + β2(race = non-white) + β3(age = 50–59 years) + β4(age = 60–74 years) + β5(age = 75+ years) + β6(birth cohort = prior to 1920)], E is cumulative chrysotile exposure (in fibre-years/ml), α = 0.9 (estimated iteratively), and β = (β7 + β8(age = 50–59 years) + β9(age = 60–74 years) + β10(age = 75+ years)). | |||||
| †Likelihood ratio χ2 statistic, degrees of freedom, p value. | |||||
| Intercept | β0 | −14.4 | 1.94 | – | |
| Sex | Male | Ref | – | – | 10.5, 1, 0.0012 |
| Female | β1 | −0.938 | 0.299 | ||
| Race | White | Ref | – | – | 11.9, 1, 0.0006 |
| Non-white | β2 | −1.20 | 0.390 | ||
| Age | <50 years | Ref | – | – | 20.4, 3, 0.0001 |
| 50–59 years | β3 | 1.06 | 2.59 | ||
| 60–74 years | β4 | 3.32 | 2.14 | ||
| 75+ years | β5 | 6.62 | 2.07 | ||
| Birth cohort | 1920+ | Ref | – | – | 5.54, 1, 0.019 |
| <1920 | β6 | 0.811 | 0.373 | ||
| Exposure | Fibre-years/ml; no lag | α | 0.9 | – | – |
| β7 | 1.52 | 0.417 | 95.5, 1, <0.0001 | ||
| Exposure×age | <50 years | Ref | – | – | 9.30, 3, 0.026 |
| 50–59 years | β8 | −0.0175 | 0.540 | ||
| 60–74 years | β9 | −0.314 | 0.456 | ||
| 75+ years | β10 | −0.897 | 0.451 | ||