[1] Univ Penn, Robert Wood Johnson Fdn Clin Scholars Program, Philadelphia, PA 19104 USA
[2] Univ Penn, Childrens Hosp Philadelphia, Div Adolescent Med, Philadelphia, PA 19104 USA
[3] Univ Penn, Dept Biostat & Epidemiol, Philadelphia, PA 19104 USA
[4] Univ Penn, Childrens Hosp Philadelphia, PolicyLab, Div Gen Pediat, Philadelphia, PA 19104 USA