Prevalence and Identification of Abnormal Lipoprotein Levels in a Biracial Population Aged 23 to 35 Years (The CARDIA Study)**This study was supported by Contracts NO1-HC-48047, NO1-HC-48048, NO1-HC-48049, and NO1-HC-48050 from the National Heart, Lung, and Blood Institute, Bethesda, Maryland