[1] Childrens Hosp, Div Adolescent Med, Boston, MA 02115 USA
[2] Harvard Univ, Sch Med, Dept Pediat, Boston, MA 02115 USA
[3] Harvard Univ, Sch Med, Dept Populat Med, Obes Prevent Program, Boston, MA USA
[4] Harvard Pilgrim Hlth Care Inst, Boston, MA USA
[5] Harvard Univ, Sch Publ Hlth, Dept Soc Human Dev & Hlth, Boston, MA 02115 USA
[6] Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA
[7] Childrens Hosp, Div Gen Pediat, Boston, MA 02115 USA