1. Department of Clinical Therapeutics, “Alexandra” Hospital National and Kapodistrian University of Athens Athens 11528 Greece
2. School of Biomedical Engineering and Imaging Sciences King's College London London SE5 9NU UK
3. School of Medicine University of Athens Athens 11527 Greece
4. Department of Biostatistics and Research Support, Julius Center for Health Sciences and Primary Care University Medical Center Utrecht Utrecht 3508 GA The Netherlands