[1] Univ Washington, Sch Med, Dept Pediat, Seattle, WA 98145 USA
[2] Massachusetts Gen Hosp Children, Dept Pediat, Div Gen Acad Pediat, Boston, MA 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 Nutr, Boston, MA 02115 USA
[6] YMCA USA, Hlth Living Dept, Chicago, IL USA
[7] Harvard Univ, Sch Publ Hlth, Dept Soc Human Dev & Hlth, Boston, MA 02115 USA
[8] Univ Michigan Hlth Syst, Div Gen Pediat, Child Hlth Evaluat & Res Unit, Ann Arbor, MI USA