[1] Univ Iowa Hosp & Clin, Dept Otolaryngol, Iowa City, IA 52242 USA
[2] Harvard Med Sch, Boston Childrens Hosp, Dept Otolaryngol, Boston, MA 02115 USA
[3] Univ Colorado, Dept Otolaryngol Head & Neck Surg, Sch Med, Aurora, CO USA
[4] Univ Calif San Diego, Rady Childrens Hosp San Diego, Div Pediat Otolaryngol, San Diego, CA 92103 USA
[5] McGill Univ, Dept Otolaryngol Head & Neck Surg, Montreal, PQ, Canada
[6] Univ Hosp Lille, Dept Pediat Otolaryngol Head Neck Surg, Lille, France
[7] Emory Univ, Sch Med, Dept Otolaryngol Head & Neck Surg, Atlanta, GA USA
[8] Great Ormond St Hosp Children NHS Fdn Trust, Dept Ear Nose & Throat Surg, London, England
[9] Natl Taiwan Univ, Coll Med, Dept Otolaryngol, Taipei, Taiwan
[10] Natl Taiwan Univ Hosp, Taipei, Taiwan
[11] Northwestern Univ, Ann & Robert H Lurie Childrens Hosp Chicago, Div Pediat Otolaryngol, Feinberg Sch Med, Chicago, IL 60611 USA
[12] UT Southwestern Med Ctr, Otolaryngol Head & Neck Surg, Dallas, TX USA
[13] Paris Univ, Necker Enfants Malad Hosp, Pediat Otolaryngol Head & Neck Surg, Paris, France
[14] NYU Langone, Dept Otolaryngol, New York, NY USA
[15] Univ Texas Houston, Dept Otorhinolaryngol, Houston, TX USA
[16] Childrens Hlth Ireland, Dept Paediat Otolaryngol, Crumlin, Ireland
[17] Cincinnati Childrens Hosp Med Ctr, Div Pediat Otolaryngol, FRACS, Cincinnati, OH 45229 USA
[18] Stanford Univ, Dept Otolaryngol Head & Neck Surg, Div Pediat Otolaryngol, Stanford, CA 94305 USA
[19] Sydney Childrens Hosp, Dept Otolaryngol, Randwick, NSW, Australia
[20] Bambino Gesu Pediat Hosp, Pediat Surg Dept, Airway Surg Unit, Rome, Italy
[21] Childrens Natl Hlth Syst, Dept Otolaryngol, Washington, DC USA
[22] Univ N Carolina, Div Pediat Otolaryngol Head & Neck Surg, Chapel Hill, NC 27515 USA