[1] Duke Univ, Duke Ctr Childhood Obes Res, Sch Med, Durham, NC 27705 USA
[2] Duke Univ, Dept Pediat, Sch Med, Durham, NC 27705 USA
[3] Univ N Carolina, Gillings Sch Global Publ Hlth, Dept Epidemiol, Chapel Hill, NC 27515 USA
[4] Dataworks NC, Durham, NC USA
[5] Duke Univ, Dept Populat Hlth Sci, Durham, NC 27705 USA
[6] Duke Clin Res Inst, Ctr Predict Med, Durham, NC USA