1. Department of Otolaryngology-Head and Neck Surgery; The Freeman Hospital; Newcastle-upon-Tyne UK
2. Institute of Health and Society; Newcastle University; Newcastle UK
3. Department of Speech and Language Therapy; Sunderland Royal Hospital; Sunderland UK
4. Department of Otolaryngology-Head and Neck Surgery; Sunderland Royal Hospital; Sunderland UK
5. Department of Otolaryngology-Head and Neck Surgery; Leeds General Infirmary; Leeds UK