1. Population Health Sciences Institute, Newcastle University Centre for Cancer, Newcastle University, Newcastle NE1 7RU, UK
2. Speech & Language Therapy, Sunderland Royal Hospital, South Tyneside and Sunderland NHS Foundation Trust, Sunderland SR4 7TP, UK
3. Speech and Language Therapy Research Unit, Southmead Hospital North Bristol NHS Hospital Trust, Bristol BS10 5NB, UK
4. Head & Neck 5000 Study, Weston NHS Foundation Trust, University of Bristol, Bristol BS8 1TU, UK
5. Liverpool Head and Neck Centre, School of Health Science, University of Liverpool, Liverpool L69 3BG, UK