Fitting a shared frailty illness-death model to left-truncated semi-competing risks data to examine the impact of education level on incident dementia.

As illustrated by our analysis of Kaiser data, our proposed modeling framework allows the analyst to assess the impact of covariates on semi-competing risks data, such as incident dementia and death, while accounting for dependence between the outcomes when data are left-truncated, as is common in studies of aging and dementia.