Dataset for: Incorporation of the time-aspect into the liability-threshold model for case-control-family data

Familial aggregation and the role of genetic and environmental factors can be investigated through family studies analysed using the liability-threshold model. The liability-threshold model ignores the timing of events including age of disease onset and right-censoring, which can lead to estimates that are difficult to interpret and potentially biased. We incorporate the time-aspect into the liability-threshold model for case-control-family data following the same approach that has been applied in twin setting. Thus, the data are considered as arising from a competing risks setting and inverse probability of censoring weights (IPCWs) are used to adjust for right-censoring. In the case-control-family setting, recognising the existence of competing events is highly relevant to the sampling of control probands. Due to the presence of multiple family members who may be censored at different ages, estimation of IPCWs is not as straightforward as in the twin setting but requires consideration. We propose to employ a composite likelihood conditioning on proband status that markedly simplifies adjustment for right-censoring. We assess the proposed approach using simulation studies and apply it in analysis of two Danish register-based case-control-family studies: one on cancer diagnosed in childhood and adolescence, and one on early onset breast cancer.