title: Hospital volume and mortality of very low-birthweight infants in South America.
abstract: OBJECTIVE
  To assess the effects of hospital volume of very low-birthweight (VLBW) infants on in-hospital mortality of VLBW and very preterm birth (VPB) infants in South America.
  
  
  METHODS
  Birth-registry data for infants born in 1982-2008 at VLBW or very preterm in 66 hospitals in Argentina, Brazil, and Chile.
  
  
  METHODS
  Regression analyses that adjust for several individual-level demographic, socioeconomic, and health factors; hospital-level characteristics; and country-fixed effects are employed.
  
  
  METHODS
  Physicians interviewed mothers before hospital discharge and abstracted hospital medical records using similar methods at all hospitals.
  
  
  RESULTS
  Volume has significant nonlinear beneficial effects on VLBW and VPB in-hospital survival. The largest survival benefits--more than 80 percent decrease in mortality rates--are with volume increases from low to medium or medium-high levels (from ≤ 25 to 72 infants annually) with significantly lower incremental benefits thereafter. The cumulative volume effects are maximized at the 121-144 annual VLBW infant range--about 90 percent decrease in mortality rates compared to <25 VLBW infants annually.
  
  
  CONCLUSIONS
  Increasing the access of pregnancies at-risk of VLBW and VPB to medium- or high-volume hospitals up to 144 VLBW infants per year may substantially improve in-hospital infant survival in the study countries.
authors.affiliation: Department of Health Management and Policy, University of Iowa, E205 GH, 200 Hawkins Drive, Iowa City, IA 52242, USA. george-wehby@uiowa.edu
authors.forename: George L
authors.initials: GL
authors.lastname: Wehby
authors.forename: Jorge
authors.initials: J
authors.lastname: Lopez-Camelo
authors.forename: Eduardo E
authors.initials: EE
authors.lastname: Castilla
mesh_terms: D019540:Area Under Curve; D001118:Argentina / Q000453:epidemiology; D001938:Brazil / Q000453:epidemiology; D002677:Chile / Q000453:epidemiology; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D007407:Interviews as Topic; D008297:Male; D012372:ROC Curve; D012042:Registries; D012044:Regression Analysis