[1] Tulane Univ, Sch Med, Dept Pediat, New Orleans, LA 70112 USA
[2] Ctr Biostat AIDS Res, Boston, MA USA
[3] Harvard TH Chan Sch Publ Hlth, Dept Epidemiol, Boston, MA USA
[4] Harvard Med Sch, Brigham & Womens Hosp, Boston, MA 02115 USA
[5] Northwestern Feinberg Sch Med, Dept Pediat, Chicago, IL USA
[6] Univ Colorado, Sch Med, Dept Pediat, Aurora, CO USA
[7] Univ Miami, Dept Pediat, Miller Sch Med, Miami, FL 33152 USA
[8] Harvard Med Sch, Dept Pediat, Boston, MA 02115 USA
[9] Univ Montreal, Dept Pediat, Montreal, PQ, Canada