[1] Baylor Coll Med, Childrens Nutr Res Ctr, Dept Pediat, Houston, TX 77030 USA
[2] Univ Tennessee, Ctr Hlth Sci, Dept Prevent Med, Memphis, TN 38163 USA
[3] HealthPartners Res Fdn, Minneapolis, MN USA
[4] Univ Minnesota, Sch Publ Hlth, Div Epidemiol, Minneapolis, MN 55455 USA
[5] Univ Memphis, Ctr Community Hlth, Memphis, TN 38152 USA
[6] NHLBI, Div Epidemiol & Clin Applicat, Bethesda, MD 20892 USA