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[Birth weight and size: charts and equations]
L-J Salomon1, J-P Bernard, B de Stavola
1Medical Statistics Unit, London School of Hygiene and Tropical Medicine, Keppel street, London WC1E 7HT, Royaume-Uni.
Journal De Gynecologie, Obstetrique Et Biologie De La Reproduction
|January 27, 2007
Summary
New French reference charts and equations for newborn birth weight and size were created using a large dataset. These updated biometrics charts and equations are more relevant for clinical practice.
Area of Science:
- Obstetrics and Gynecology
- Pediatrics
- Biostatistics
Background:
- Accurate reference charts for birth weight and size are crucial for assessing newborn health.
- Existing reference charts may not reflect current population demographics or be based on sufficiently large datasets.
Purpose of the Study:
- To develop new, comprehensive reference charts and equations for birth weight and size.
- To compare these new references with previously established ones.
- To provide updated tools for clinical assessment of newborns.
Main Methods:
- Utilized a large dataset from the Yvelines birth registry (over 3 years).
- Employed high-order polynomial least squares regression models.
- Calculated Z-scores for birth weight and size across gestational ages (25-42 weeks), adjusted for sex.
Main Results:
- Included 58,934 birth weight and 56,956 birth size measurements.
- Generated new charts and predictive equations based on polynomial regression.
- These results provide sex-adjusted Z-score calculations.
Conclusions:
- Presents new French reference charts and equations for neonatal biometrics.
- The large, unselected sample enhances clinical relevance.
- Easily applicable for computing centiles and Z-scores in practice.
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