It was possible, using Cox models, to correct for the waiting-time bias, but the strong protective effect of termination of hospitalization on the risk for infection remained difficult to interpret.

The Cox regression model with a shared frailty factor allows for unobserved heterogeneity or for statistical dependence between the observed survival times. Estimation in this model when the frailties ...

Although Cox and logistic regression models have been compared previously in cohort studies, this work does not completely cover the GWAS setting nor extend to the case-cohort study design.