1. Division of Neonatology Health Research Institute i + 12 University Hospital 12 de Octubre Universidad Complutense Madrid Spain
2. Division of Neonatology University Hospital Cruces Barakaldo Spain
3. Division of Neonatology University Hospital de Salamanca Salamanca Spain
4. Division of Neonatology Hospital de la Santa Creu I Sant Pau Barcelona Spain
5. Division of Neonatology Hospital de Algeciras Cádiz Spain
6. Primary Care Paediatrician Health Care Center Goya Madrid Spain
7. Primary Care Paediatrician Health Care Center Fuensanta Valencia Spain
8. Division of Neonatology University Hospital 12 de Octubre Madrid Spain
9. Division of Neonatology University and Polytechnic Hospital La Fe Valencia Spain