The Collaborative Lipid Research Clinics Program Family Study. I. Study design and description of data.

The third phase of the Lipid Research Clinics North American Population Studies is the Collaborative Family Study (1975-1978), designed to contribute knowledge of the familial association of dyslipoproteinemia and distribution of lipids and lipoproteins among family members. The 2,405 probands of the study were composed of a random (40%) and a hyperlipidemic (60%) component. A total of 15,693 living relatives of these probands were identified, of whom about 75% participated in the study. Demographic, medical, and medication history and lipid and lipoprotein data were collected with strict adherence to a common protocol and standardized laboratory methodology. This report presents the design and scope of the Family Study and the distribution of probands and relatives by clinic, age, selection scheme, and family structure. The possible avenues of analysis and the potential usefulness of this large, high quality data base in assessing the familial determinants of lipid and lipoprotein levels are discussed.