[1] Tufts Univ, Friedman Sch Nutr Sci & Policy, 150 Harrison Ave, Boston, MA 02111 USA
[2] St Jude Childrens Res Hosp, Dept Epidemiol & Canc Control, 332 N Lauderdale St, Memphis, TN 38105 USA
[3] St Jude Childrens Res Hosp, Dept Oncol, 332 N Lauderdale St, Memphis, TN 38105 USA
[4] St Jude Childrens Res Hosp, Dept Global Pediat Med, 332 N Lauderdale St, Memphis, TN 38105 USA
[5] St Jude Childrens Res Hosp, Dept Psychol, 332 N Lauderdale St, Memphis, TN 38105 USA
[6] JPS Hlth Network, Ctr Outcomes Res, Ft Worth, TX USA