1. Department of Biomedical Sciences, University of Sassari, Sassari, Italy
2. Department of Medical, Surgical, and Experimental Sciences, Ophthalmology Unit, University of Sassari, Sassari, Italy
3. Azienda Ospedaliero-Universitaria (AOU) di Sassari, Sassari, Italy
4. Department of Biomedical Sciences, Clinical Epidemiology and Medical Statistics Unit, University of Sassari, Sassari, Italy