1. A.O.U. Città della Salute e della Scienza di Torino, Regina Margherita Children’s Hospital, Department of Pediatric Emergency, Pediatric Headache Centre, Turin, Italy
2. Unit of Cancer Epidemiology, Department of Medical Sciences, University of Turin, Turin, Italy
3. Unit of Epidemiology, Regional Health Service, ASL TO3, Grugliasco (TO), Italy