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Generating expected growth curves and Z-scores for premature infants

W R Riddle1, S C DonLevy

  • 1Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232-2675, USA. bill.riddle@vanderbilt.edu

Journal of Perinatology : Official Journal of the California Perinatal Association
|March 19, 2010
PubMed

Insights

This study establishes a standard for premature infant growth, creating Z-scores for weight, head circumference, and length. These Z-scores help track the growth of premature infants against established norms.

Area of Science:

  • Neonatalogy
  • Pediatric Growth Standards
  • Biostatistics

Background:

  • Premature infants require specific growth monitoring.
  • Existing growth charts may not accurately reflect premature infant development.

Purpose of the Study:

  • Establish a standard for premature infant growth.
  • Generate Z-scores for key growth parameters.

Main Methods:

  • Utilized multiple regression and analysis of variance.
  • Compared percentiles (10th, 50th, 90th) from various studies against Riddle's data.
  • Generated Z-scores from established percentiles.

Main Results:

  • Growth charts from Mead-Johnson, Babson, Williams, Alexander, Usher, Yudkin, and Fenton were not coincident with Riddle's data.
  • Thomas's reported percentiles were statistically coincident with Riddle's data.

Conclusions:

  • Regression equations for 10th, 50th, and 90th percentiles provide expected premature infant growth.
  • These equations enable the generation of expected growth curves and Z-scores for weight, head circumference, and length.
Abstract

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