| Parameter | Type of distribution |
| Base model: | |
| Relative risk of mortality in current smokers and former smokers compared to never smokers | Log normal |
| Prevalence of current, former and never smokers | Dirichlet |
| Forecasting model: | |
| Relative risk of mortality in current smokers and former smokers compared to never smokers | Log normal |
| Cessation rate | Beta |
| Average yearly rate of decline in smoking initiation | Beta |