[1] G Gaslini Inst Children, Pulm Dis Unit, I-16147 Genoa, Italy
[2] Univ Cagliari, Neonatal Intens Care Unit, Cagliari, Italy
[3] Univ Naples Federico II, Dept Pediat, Naples, Italy
[4] Univ Cattolica Sacro Cuore, Dept Neonatol, I-00168 Rome, Italy
[5] Umberto I Hosp, Div Neonatol, Enna, Italy
[6] Monteluce Policlin, Dept Gynecol Obstet & Pediat, Perugia, Italy
[7] Maggiore Carita Hosp, Dept Pediat, Novara, Italy
[8] Perrino Hosp, Div Neonatol, Brindisi, Italy
[9] GB Grassi Hosp, Div Pediat, Rome, Italy
[10] Umberto I Hosp, Neonatal Intens Care Unit, Nocera, Italy
[11] Thiene Hosp, Div Pediat, Thiene, Italy
[12] Univ Vita Salute San Raffaele, Div Pediat & Neonatol, Milan, Italy
[13] Abbott Italy, Latina, Italy