title: The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study.
abstract: OBJECTIVE
  To examine the effects of designation and volume of neonatal care at the hospital of birth on mortality and morbidity outcomes in very preterm infants in a managed clinical network setting.
  
  
  METHODS
  A retrospective, population-based analysis of operational clinical data using adjusted logistic regression and instrumental variables (IV) analyses.
  
  
  METHODS
  165 National Health Service neonatal units in England contributing data to the National Neonatal Research Database at the Neonatal Data Analysis Unit and participating in the Neonatal Economic, Staffing and Clinical Outcomes Project.
  
  
  METHODS
  20 554 infants born at <33 weeks completed gestation (17 995 born at 27-32 weeks; 2559 born at <27 weeks), admitted to neonatal care and either discharged or died, over the period 1 January 2009-31 December 2011.
  
  
  METHODS
  Tertiary designation or high-volume neonatal care at the hospital of birth.
  
  
  RESULTS
  Neonatal mortality, any in-hospital mortality, surgery for necrotising enterocolitis, surgery for retinopathy of prematurity, bronchopulmonary dysplasia and postmenstrual age at discharge.
  
  
  RESULTS
  Infants born at <33 weeks gestation and admitted to a high-volume neonatal unit at the hospital of birth were at reduced odds of neonatal mortality (IV regression odds ratio (OR) 0.70, 95% CI 0.53 to 0.92) and any in-hospital mortality (IV regression OR 0.68, 95% CI 0.54 to 0.85). The effect of volume on any in-hospital mortality was most acute among infants born at <27 weeks gestation (IV regression OR 0.51, 95% CI 0.33 to 0.79). A negative association between tertiary-level unit designation and mortality was also observed with adjusted logistic regression for infants born at <27 weeks gestation.
  
  
  CONCLUSIONS
  High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very preterm infants. Future developments of neonatal services should promote delivery of very preterm infants at hospitals with high-volume neonatal units.
authors.affiliation: Warwick Medical School, University of Warwick, Coventry, UK.
authors.forename: S I
authors.initials: SI
authors.lastname: Watson
authors.affiliation: Department of Economics, University of Warwick, Coventry, UK.
authors.forename: W
authors.initials: W
authors.lastname: Arulampalam
authors.affiliation: Warwick Medical School, University of Warwick, Coventry, UK.
authors.forename: S
authors.initials: S
authors.lastname: Petrou
authors.affiliation: Academic Neonatology, UCL Institute for Women's Health, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Marlow
authors.affiliation: Academic Neonatology, UCL Institute for Women's Health, London, UK.
authors.forename: A S
authors.initials: AS
authors.lastname: Morgan
authors.affiliation: Department of Health Sciences, University of Leicester, Leicester, UK.
authors.forename: E S
authors.initials: ES
authors.lastname: Draper
authors.affiliation: Section of Neonatal Medicine, Department of Medicine, Chelsea and Westminster Campus, Imperial College London, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Santhakumaran
authors.affiliation: Section of Neonatal Medicine, Department of Medicine, Chelsea and Westminster Campus, Imperial College London, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Modi
mesh_terms: D015331:Cohort Studies; D004739:England / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000453:epidemiology* / Q000401:mortality; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data*; D008297:Male; D012189:Retrospective Studies