1. The Irish Longitudinal Study on Ageing (TILDA), Department of Medical Gerontology, Trinity College Dublin, Ireland.
2. Department of Optometry, Dublin Institute of Technology, Ireland.
3. African Vision Research Institute, University of KwaZulu Natal, Durban, South Africa.
4. Department of Medical Physics and Bioengineering, Mercer’s Institute for Successful Ageing, St. James’s Hospital, Dublin, Ireland.