1 Faculty of Life Sciences and Medicine, King's College London, London WC2R 2LS, UK; King's Ophthalmology Research Unit, King's College Hospital, London, UK. Electronic address: t.jackson1@nhs.net.
2 Health Economics Research Centre, University of Oxford, Oxford, UK.
3 Population Health Sciences, King's College London, London, UK.
4 Bristol Medical School, University of Bristol, Bristol, UK.
5 King's Ophthalmology Research Unit, King's College Hospital, London, UK.
6 Faculty of Life Sciences and Medicine, King's College London, London WC2R 2LS, UK.
7 Faculty of Life Sciences and Medicine, King's College London, London WC2R 2LS, UK; King's Ophthalmology Research Unit, King's College Hospital, London, UK.