Relative risks in copper cadmium alloy workers for cancer of the lung and chronic disease of the respiratory system by level of cumulative exposure, from Poisson regression modelling (Sorahan et al 1995)26
|
Cumulative exposure to cadmium (μg.m-3.y) | Deaths n | RR9-152 (95% CI) |
Likelihood ratio test9-153 p value | RR 9-154 (95% CI) |
Likelihood ratio test9-153 p value |
| Cancer of lung9-164: | |||||
| <1600 | 10 | 1.0 | 1.0 | ||
| 1600– | 5 | 0.50 (0.17 to 1.46) | 0.85 (0.27 to 2.68) | ||
| ⩾4800 | 4 | 0.46 (0.14 to 1.49) | 0.289 | 0.81 (0.18 to 3.73) | 0.947 |
| Evaluation of trend9-161 | 0.65 (0.36 to 1.18) | 0.144 | 0.89 (0.43 to 1.84) | 0.753 | |
| Chronic diseases of respiratory system (non-malignant)9-162: | |||||
| <1600 | 8 | 1.0 | 1.0 | ||
| 1600– | 28 | 3.469-160(1.58 to 7.59) | 4.549-165 (1.96 to 10.51) | ||
| ⩾4800 | 24 | 3.329-160 (1.48 to 7.42) | 0.001 | 4.749-160 (1.81 to 12.43) | <0.001 |
| Evaluation of trend | 1.619-160 (1.15 to 2.23) | 0.004 | 1.969-160 (1.27 to 3.02) | 0.002 | |
9-150 P<0.05;
↵9-160 P<0.01;
↵9-165 P<0.001.
9-151 Based on the mortality experience of the 347 copper cadmium alloy workers.
↵9-152 Adjustment for age.
↵9-153 Difference between the deviance for a model that includes the variable cumulative exposure to cadmium and the deviance for a model that excludes this variable. This difference is interpreted as a χ2 value with degrees of freedom equal to the number of terms added to the fuller model (three terms for the analyses by level of exposure, or one term for the analyses which evaluated trends).
↵9-154 Adjustment for age, year of start of alloy work, factory, and time since starting alloy work.
↵9-164 ICD-8, 162-163, underlying or contributory cause.
↵9-161 Relative risk for change in exposure of one level.
↵9-162 ICD-8, 490-519, underlying or contributory cause.