1. Erik. J. Rodriquez is with the Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD. Eliseo J. Pérez-Stable is with the Office of the Director, National Institute on Minority Health and Health Disparities and the Division of Intramural Research, National Heart, Lung, and Blood Institute, National Institutes of Health.