1. Department of Ophthalmology, University of Turin, 10126 Turin, Italy
2. Department of Psychology, University of Turin, 10124 Turin, Italy
3. Department of Ophthalmology, University of Catania, 95123 Catania, Italy
4. Department of General Ophthalmology, Medical University of Lublin, 20079 Lublin, Poland
5. Eye Clinic, Public Health Department, Federico II University, 80131 Naples, Italy
6. Department of Ophthalmology, Beauregard Hospital, 11100 Aosta, Italy