[1] Univ Utah, Sch Med, Dept Pediat, Salt Lake City, UT USA
[2] Primary Childrens Med Ctr, Salt Lake City, UT 84103 USA
[3] Univ Colorado, Hlth Sci Ctr, Dept Pediat, Denver, CO 80262 USA
[4] Columbia Univ, Coll Phys & Surg, New York, NY USA
[5] Univ S Florida, Dept Pediat, St Petersburg, FL 33701 USA
[6] Washington Univ, Dept Pediat, St Louis, MO 63130 USA
[7] Univ Texas, SW Med Ctr, Dept Pediat, Dallas, TX USA
[8] Wayne State Univ, Sch Med, Dept Pediat, Detroit, MI 48201 USA
[9] Northwestern Univ, Dept Pediat, Feinberg Sch Med, Chicago, IL 60611 USA
[10] Harvard Univ, Sch Med, Dept Pediat, Boston, MA 02115 USA
[11] Vanderbilt Univ, Sch Med, Dept Pediat, Nashville, TN 37212 USA
[12] Stanford Univ, Med Ctr, Dept Pediat, Stanford, CA 94305 USA
[13] GlaxoSmithKline Inc, Philadelphia, PA USA