[1] Univ Michigan, Mott Childrens Hosp, Dept Otolaryngol Head & Neck Surg, Med Ctr, Ann Arbor, MI USA
[2] Univ Michigan, Sch Publ Hlth, Dept Epidemiol, Ann Arbor, MI USA
[3] Univ Michigan, Susan B Meister Child Hlth Evaluat & Res Ctr, Dept Pediat, Ann Arbor, MI USA
[4] Michigan Med, Dept Otolaryngol Head & Neck Surg, 1500 E Med Ctr Dr, Ann Arbor, MI 48109 USA