European Journal of Epidemiology

, Volume 23, Issue 3, pp 163–166 | Cite as

From causal diagrams to birth weight-specific curves of infant mortality

  • Sonia Hernández-Díaz
  • Allen J. Wilcox
  • Enrique F. Schisterman
  • Miguel A. Hernán


This report explores the low birth weight paradox using two graphical approaches: causal directed acyclic graphs (DAGs), and the empirical curves of the birth weight distribution and birth weight-specific mortality. The birth weight curves are able to represent the associations quantitatively, while the corresponding causal DAGs provide a set of plausible explanations for the findings. Taken together, these two approaches can facilitate discussion of underlying biological mechanisms.


Birth weight Mortality Curves DAGs Paradox 


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Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Sonia Hernández-Díaz
    • 1
  • Allen J. Wilcox
    • 2
  • Enrique F. Schisterman
    • 3
  • Miguel A. Hernán
    • 1
  1. 1.Department of EpidemiologyHarvard School of Public HealthBostonUSA
  2. 2.Epidemiology Branch, National Institute of Environmental Health SciencesNational Institutes of HealthDurhamUSA
  3. 3.Epidemiology Branch, National Institute of Child Health and Human DevelopmentNational Institutes of HealthBethesdaUSA

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