title: Examining the effect of hospital-level factors on mortality of very low birth weight infants using multilevel modeling.
abstract: OBJECTIVE
  The objective of this study was to examine the effect of hospital-level factors on mortality of very low birth weight infants using multilevel modeling.
  
  
  METHODS
  This is a secondary data analysis of California maternal-infant hospital discharge data from 1997 to 2002. The study population was limited to singleton, non-anomalous, very low birth weight infants, who delivered in hospitals providing neonatal intensive care services (level-2 and higher). Hierarchical generalized linear modeling, also known as multilevel modeling, was used to adjust for individual-level confounders.
  
  
  RESULTS
  In a multilevel model, increasing hospital volume of very low birth weight deliveries was associated with lower odds of very low birth weight mortality. Characteristics of a particular hospital's obstetrical and neonatal services (the presence of residency and fellowship training programs and the availability of perinatal and neonatal services) had no independent effect.
  
  
  CONCLUSIONS
  Using multilevel modeling, hospital volume of very low birth weight deliveries appears to be the primary driver of reduced mortality among very low birth weight infants.
authors.affiliation: Department of Obstetrics and Gynecology, University of California, Orange, CA 92868, USA. judithc@uci.edu
authors.forename: J H
authors.initials: JH
authors.lastname: Chung
authors.forename: C S
authors.initials: CS
authors.lastname: Phibbs
authors.forename: W J
authors.initials: WJ
authors.lastname: Boscardin
authors.forename: G F
authors.initials: GF
authors.lastname: Kominski
authors.forename: A N
authors.initials: AN
authors.lastname: Ortega
authors.forename: K D
authors.initials: KD
authors.lastname: Gregory
authors.forename: J
authors.initials: J
authors.lastname: Needleman
mesh_terms: D002140:California / Q000453:epidemiology; D006761:Hospitals / Q000706:statistics & numerical data*; D006784:Hospitals, Teaching / Q000706:statistics & numerical data; D006801:Humans; D007226:Infant Mortality; D007231:Infant, Newborn; D019102:Infant, Very Low Birth Weight; D007363:Intensive Care Units, Neonatal / Q000706:statistics & numerical data; D015233:Models, Statistical; D016017:Odds Ratio