1. Department of Neonatology, Hospital General Universitario Gregorio Marañón and Complutense University of Madrid, Madrid, Spain;
2. Neonatology Service, Department of Pediatrics, Hospital Central Universitario de Asturias, Oviedo, Spain;
3. Neonatology Service, Hospital Universitario 12 de Octubre, Madrid, Spain;
4. Department of Neonatology, Hospital Sant Joan de Déu Barcelona, Barcelona, Spain;
5. Neonatology Service, Department of Pediatrics, Hospital Clínico Universitario de Santiago, Santiago de Compostela, Spain;
6. Department of Neonatology, Hospital Universitari Vall d’Hebron and Universitat Autònoma de Barcelona, Barcelona, Spain;
7. Division of Neonatology, Hospital Universitari i Politècnic La Fe, Valencia, Spain;
8. Department of Neonatology, Hospital Universitario Miguel Servet, Zaragoza, Spain;
9. Department of Neonatology, Hospital Regional Universitario de Málaga, Málaga, Spain;
10. Neonatology Service, Hospital Universitario de Cruces, Barakaldo, Spain; and
11. Department of Neonatology, Hospital Universitario La Paz, Madrid, Spain