1. From the Center for American Indian Health Research (Y.Z., E.T.L., J.Y.), College of Public Health, University of Oklahoma, Health Sciences Center, Oklahoma City; Cornell University Medical Center (R.B.D.), New York, NY; Missouri Breaks Industries Research, Inc (L.G.B.), Timber Lake, SD; Epidemiology and Biometry Program (R.R.F.), National Heart, Lung, and Blood Institute, Bethesda, MD; and MedStar Research Institute (B.V.H.), Washington, DC.