[1] Univ Penn, Dept Otorhinolaryngol Head & Neck Surg, Philadelphia, PA 19104 USA
[2] Temple Univ, Lewis Katz Sch Med, Philadelphia, PA USA
[3] Univ Penn, Perelman Sch Med, Philadelphia, PA USA
[4] Univ Penn, Dept Anesthesiol & Crit Care, Philadelphia, PA USA
[5] Univ Penn, Leonard Davis Inst Hlth Econ, Philadelphia, PA USA