1. Neonatal Division Department of Perinatal and Neonatal Medicine Jichi Medical University Saitama Medical Center SaitamaJapan
2. Saitama Medical Center Saitama Medical University SaitamaJapan
3. National Center for Child Health and Development TokyoJapan
4. Toyohashi Municipal Hospital AichiJapan
5. St Luke’s International Hospital TokyoJapan
6. Kagoshima City Hospital Kagoshima Japan