1. School of Optics and Optometry, Universidad Complutense de Madrid, Madrid, Spain
2. Ramón y Cajal University Hospital, Ramón y Cajal Health Research Institute (IRYCIS) and Clínica Rementería, Madrid, Spain
3. Aragon Institute for Health Research (IIS Aragon), Zaragoza, Spain; Department of Ophthalmology, Hospital Clinico Universitario, Zaragoza, Spain
4. Dos de Maig Hospital, Barcelona, Catalunya, Spain
5. Virgen de la Victoria University Hospital, Málaga, Andalucía, Spain
6. Independent Health Services Researcher, Madrid, Spain