[1] Univ N Carolina Chapel Hill, Dept Epidemiol, Chapel Hill, NC 27599 USA
[2] Univ N Carolina Chapel Hill, Dept Psychol, Chapel Hill, NC 27599 USA
[3] Cincinnati Childrens Hosp & Med Ctr, Dept Pediat, Div Rheumatol, James M Anderson Ctr Hlth Syst Excellence, Cincinnati, OH USA
[4] Northwestern Univ, Feinberg Sch Med, Dept Med Social Sci, Chicago, IL 60611 USA
[5] Univ Washington, Ctr Outcomes Res Rehabil, Seattle, WA 98195 USA
[6] Texas A&M Univ, Coll Med, Dept Landscape Architecture & Urban Planning, Dept Pediat, College Stn, TX 77843 USA
[7] Univ N Carolina Chapel Hill, Div Gen Med & Clin Epidemiol, Chapel Hill, NC 27599 USA
[8] Univ N Carolina Chapel Hill, Cecil G Sheps Ctr Hlth Serv Res, Chapel Hill, NC 27599 USA