Evaluation of variation in exposure effect with time since exposure under three exposure weighting functions. Canadian nuclear industry workers study
| Exposure weight function | Residual deviance | Likelihood ratio statistic* | Degrees of freedom | p Value |
|---|---|---|---|---|
| *Test for variation in exposure effect with time since exposure. Model fit is compared to the model for total cumulative dose (that is, η = 0 for the step function; σ1 = 1 for the sigmoid function; and, φ1 = φ2 = 0 for the bilinear function with φ2 parameterised as a slope). Analyses of lung cancer, and cancers other than lung and leukaemia, were matched on attained age, sex, calendar year at risk, facility, socioeconomic status, duration of monitoring, and monitoring status; analyses of leukaemia were matched on attained age and adjusted for sex, calendar year at risk, facility, socioeconomic status, duration of monitoring, and monitoring status. | ||||
| Lung cancer | ||||
| Step function | 1237.25 | 1.91 | 1 | 0.17 |
| Sigmoid function | 1237.41 | 1.75 | 1 | 0.19 |
| Bilinear function | 1233.89 | 5.27 | 2 | 0.07 |
| Leukaemia | ||||
| Step function | 83.16 | 0.00 | 1 | 1.00 |
| Sigmoid function | 82.12 | 1.04 | 1 | 0.31 |
| Bilinear function | 82.54 | 0.62 | 2 | 0.73 |
| Cancers other than lung and leukaemia | ||||
| Step function | 2049.00 | 1.40 | 1 | 0.24 |
| Sigmoid function | 2049.07 | 1.33 | 1 | 0.25 |
| Bilinear function | 2049.16 | 1.24 | 2 | 0.54 |