[1] Childrens Hosp Philadelphia, Div Pediat Rheumatol, Philadelphia, PA 19104 USA
[2] Univ Penn, Ctr Clin Epidemiol & Biostat, Dept Biostat & Epidemiol, Philadelphia, PA 19104 USA
[3] Childrens Hosp Philadelphia, Ctr Pediat Clin Effectiveness, Philadelphia, PA 19104 USA
[4] Childrens Hosp Philadelphia, PolicyLab, Philadelphia, PA 19104 USA