1. Harrison W, Goodman D. Epidemiologic trends in neonatal intensive care, 2007-2012. JAMA Pediatr 2015;169:855–62.
2. Shin SM, Namgung R, Oh YK, Yoo BH, Jun YH, Lee KH. A survey on the current status of neonatal intensive care units for the planning of regional perinatal care system in Korea. J Korean Soc Neonatol 1996;3:1–8.
3. Han YJ, Seo K, Shin SM, Lee SW, Do SR, Chang SW. Low birth weight outcomes and policy issues in Korea. Sejong:Korea Institute for Health and Social Affairs, 1999.
4. Shin SM. Current status and a prospect of neonatal intensive care units in Korea. J Korean Med Assoc 2006;49:983–9.
5. Shin SM. Current status of neonatal intensive care units in Korea. Korean J Pediatr 2008;51:243–7.
6. Kang BH, Jung KA, Hahn WH, Shim KS, Chang JY, Bae CW. Regional analysis on the incidence of preterm and low birth weight infant and the current situation on the neonatal intensive care units in Korea, 2009. J Korean Soc Neonatol 2011;18:70–5.
7. Kim H. Evaluation of performance and efficiency in operation of neonatal intensive care unit. Sejong:Ministry of Health and Welfare, 2016.
13. Kim BI. Development of evaluation method and criteria for the appropriateness of neonatal intensive care unit. Wonju:Health Insurance Review and Assessment Service, 2017.
14. American Academy of Pediatrics Committee on Fetus and Newborn. Levels of neonatal care. Pediatrics 2012;130:587–97.
16. American Academy of Pediatrics. Committee on Fetus and Newborn. Manpower needs in neonatal pediatrics. Pediatrics 1985;76:132–5.
17. American Academy of Pediatrics. Committee on Fetus and New born. Committee of the Section on Perinatal Pediatrics. Estimates of need and recommendations for personnel in neonatal pediatrics. Pediatrics 1980;65:850–3.
18. Thompson LA, Goodman DC, Little GA. Is more neonatal intensive care always better? Insights from a cross-national comparison of reproductive care. Pediatrics 2002;109:1036–43.
19. Goodman DC, Fisher ES, Little GA, Stukel TA, Chang CH, Schoendorf KS. The relation between the availability of neonatal intensive care and neonatal mortality. N Engl J Med 2002;346:1538–44.
20. Tucker J, UK Neonatal Staffing Study Group. Patient volume, staffing, and workload in relation to risk-adjusted outcomes in a random stratified sample of UK neonatal intensive care units: a prospective evaluation. Lancet 2002;359:99–107.
21. Han SJ. High-risk maternal and newborn integrated care centers: status and issues on aspect of pediatric surgery. Korean J Perinatol 2014;25:68–74.
23. Phibbs CS, Bronstein JM, Buxton E, Phibbs RH. The effects of patient volume and level of care at the hospital of birth on neonatal mortality. JAMA 1996;276:1054–9.
24. Phibbs CS, Baker LC, Caughey AB, Danielsen B, Schmitt SK, Phibbs RH. Level and volume of neonatal intensive care and mortality in very-low-birth-weight infants. N Engl J Med 2007;356:2165–75.
27. Bartels DB, Wypij D, Wenzlaff P, Dammann O, Poets CF. Hospital volume and neonatal mortality among very low birth weight infants. Pediatrics 2006;117:2206–14.
28. Chung JH, Phibbs CS, Boscardin WJ, Kominski GF, Ortega AN, Needleman J. The effect of neonatal intensive care level and hospital volume on mortality of very low birth weight infants. Med Care 2010;48:635–44.
29. Lasswell SM, Barfield WD, Rochat RW, Blackmon L. Perinatal regionalization for very low-birth-weight and very preterm infants: a meta-analysis. JAMA 2010;304:992–1000.
30. Shim JW, Kim MJ, Kim EK, Park HK, Song ES, Lee SM, et al. The impact of neonatal care resources on regional variation in neonatal mortality among very low birthweight infants in Korea. Paediatr Perinat Epidemiol 2013;27:216–25.
33. Bae CW. Bench-marking of Japanese perinatal center system for improving maternal and neonatal outcome in Korea. Korean J Perinatol 2010;21:129–39.
36. Staebler S, Bissinger R. 2016 Neonatal nurse practitioner workforce survey: report of findings. Adv Neonatal Care 2017;17:331–6.