ABSTRACT
In many ways, familial studies simply are special cases of sampling designs in which multivariate failure times arise; however, they also have special emphases and features which are the topic of this chapter. To assist in exemplifying these, we shall carry the following example throughout this chapter: the study of dementia in the Cache County Study on Memory in Aging. Initiated in 1995, this investigation was designed to examine the prevalence of various dementias (Breitner et al., 1999). Its study design targeted the entire 65-year and older population of Cache County, Utah, U.S.A., thus provides a unique opportunity for the investigation of familial factors underlying dementia. In brief, a population-based sample of study participants was ascertained and assessed for specific dementias, as well as many other characteristics and outcomes. Then, for each participant, information was collected from all first-degree relatives, and dementia diagnoses also made on these. In all, the study
on dementia occurrence, age at onset among those experiencing the disease, and either current age or age at death for more than 5,000 family clusters.
