An overview of international literature from cystic fibrosis registries. Part 4: Update 2011. Salvatore D, Buzzetti R, Baldo E, Furnari ML, Lucidi V, Manunza D, Marinelli I, Messore B, Neri AS, Raia V, Mastella G. Journal of Cystic Fibrosis, 2012;11(6):480-493