Author contributions:
Concept/Design: Masiello, Mastrogiovanni
Data analysis: Bruno, Presutto
Drafting article: Masiello, Chivasso, Cafarelli
Critical revision: Masiello, Mastrogiovanni, Iesu
Approval of article: Iesu
Statistical: Bruno
Data collection: Presutto, Leone, Triggiani, Colombino, Miele