1 1 Department of Ophthalmology, University Hospitals Birmingham NHS Foundation Trust, Birmingham B15 2TH, UK.
2 2 Academic Unit of Ophthalmology, Institute of Inflammation & Ageing, University of Birmingham, Birmingham B15 2TT, UK.
3 3 Centre for Patient Reported Outcome Research, Institute of Applied Health Research, University of Birmingham, Birmingham B15 2TT, UK.
4 4 NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London EC1V 9EL, UK.