1. Brighton & Sussex University Hospitals NHS Trust; Sussex Eye Hospital; Eastern Road Brighton Sussex UK BN2 5BF
2. Johns Hopkins Bloomberg School of Public Health; Department of Epidemiology; 615 N. Wolfe Street Baltimore Maryland USA 21205
3. The Moorfields Eye Hospital/UCL Institute of Ophthalmology National Institute for Health Research Biomedical Research Centre; 162 City Road London UK EC1V 2PD