1. Nuffield Department of Surgical Sciences; University of Oxford; Oxford UK
2. Department of Otorhinolaryngology; Faculty of Medicine, Khon Kaen University; Khon Kaen Thailand
3. National Institute for Health and Care Excellence; Manchester UK
4. Department of Otolaryngology, Faculty of Medicine; Chulalongkorn University; Bangkok Thailand
5. Cochrane ENT; Nuffield Department of Surgical Sciences, University of Oxford; Oxford UK
6. Department of Medicine; Norwich Medical School, University of East Anglia; Norwich UK
7. ENT Department; Guy's Hospital; London UK
8. Cochrane UK; Oxford UK