[1] UCL, Res Dept Primary Care & Populat Hlth, London, England
[2] London Sch Hyg & Trop Med, Dept Med Stat, London, England
[3] Hlth Data Res UK, London, England
[4] UCL, Inst Hlth Informat, London, England
[5] UCL, MRC Clin Trials Unit UCL, London, England
[6] Univ Southampton, Primary Care & Populat Sci, Southampton, Hants, England
[7] ENT Clin, Zeist, Netherlands
[8] NIHR UCLH Biomed Res Ctr, London, England
[9] UCL, Ear Inst, London, England
[10] Univ East Anglia, Norwich Med Sch, Norwich, Norfolk, England
[11] James Paget Univ Hosp NHS Fdn Trust, ENT Dept, Great Yarmouth, England
[12] Guys & St Thomas NHS Fdn Trust, ENT Dept, London, England
[13] Univ Cambridge, Dept Publ Hlth & Primary Care, Primary Care Unit, Cambridge, England