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Construction of the birth weight by gestational age population reference curves of Catalonia (Spain): Methods and

Francisca Ramos1, Glória Pérez, Mireia Jané

  • 1Doctorate Program in Public Health and Biomedical Research of Autonomous University of Barcelona, Barcelona, Spain. pramos@ambitcp.catsalut.net

Gaceta Sanitaria
|February 24, 2009
PubMed

Insights

This study introduces new methods for creating infant birth weight reference curves, crucial for assessing fetal growth. These advanced curves accurately model newborn size variations for better clinical evaluation.

Area of Science:

  • Neonatal research
  • Pediatric anthropometry
  • Biostatistics

Background:

  • Infant size at birth is a key indicator of fetal growth relative to gestational age.
  • Standardized models for neonatal anthropometric reference curves are lacking, impacting reference value estimation.
  • Existing methods may not adequately capture complex birth weight distributions.

Purpose of the Study:

  • To describe novel methods for constructing population-based birth weight for gestational age reference curves in Catalonia, Spain.
  • To establish accurate and reliable reference standards for assessing newborn size.
  • To address limitations in existing methodologies for neonatal anthropometric data.

Main Methods:

  • Utilized a probabilistic cluster model for detecting implausible birth weight values relative to gestational age.
  • Employed the Generalized Additive Model for Location and Scale (GAMLSS) for smoothed percentile and z-score estimation.
  • Calculated 95% confidence intervals using bootstrapping for robust statistical inference.

Main Results:

  • Developed population-based reference curves for birth weight by gestational age.
  • The methodology effectively modeled asymmetric and kurtotic birth weight distributions.
  • Provided 95% confidence intervals for reference intervals, aiding in newborn size assessment.

Conclusions:

  • The described methods offer a robust approach to creating neonatal anthropometric reference curves.
  • These novel reference curves allow for the modeling of complex, non-normal fetal growth distributions.
  • Accurate reference intervals are essential for evaluating newborn size and fetal development.

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