1. Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, MN, USA (KH)
2. Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USA (EV)
3. Department of Medicine, Baylor College of Medicine, Houston, TX, USA (EV)
4. Department of Health and Human Performance, University of Houston, Houston, TX, USA (JK, CJ)