[1] Chulalongkorn Univ, Dept Otolaryngol, Fac Med, Bangkok, Thailand
[2] Chulalongkorn Univ, Biostat Excellence Ctr, Fac Med, Bangkok, Thailand
[3] Rajavithi Hosp, Ctr Excellence Otolaryngol Head & Neck Surg, Bangkok, Thailand
[4] Khon Kaen Univ, Srinagarind Hosp, Dept Otorhinolaryngol, Fac Med, Khon Kaen, Thailand
[5] Prince Songkla Univ, Dept Otolaryngol, Fac Med, Hat Yai, Thailand
[6] Phramongkutklao Hosp, Dept Otolaryngol, Bangkok, Thailand
[7] Mahidol Univ, Siriraj Hosp, Dept Otorhinolaryngol, Fac Med, Bangkok, Thailand
[8] Thammasat Univ Hosp, Dept Pediat, Ctr Excellence Allergy Asthma & Pulm Dis, Pathum Thani, Thailand