Estimating onset time from longitudinal data in the presence of measurement error with application to estimating

Ana M Ortega-Villa1, Paul S Albert1

  • 1Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.

Statistics in Medicine
|October 9, 2018
PubMed

Insights

Accurate gestational age assessment is vital for newborns. This study introduces a new model using maternal measurements to estimate gestational age, especially for low-resource settings lacking advanced technology.

Area of Science:

  • Maternal and Fetal Health
  • Biostatistics
  • Public Health

Background:

  • Accurate gestational age (GA) estimation is crucial for neonatal care and outcomes.
  • Current ultrasound-based methods for GA assessment are often inaccessible in low-resource settings.
  • Maternal anthropometry offers a potential alternative for GA estimation.

Purpose of the Study:

  • To develop and evaluate a statistical model for estimating gestational age at birth using longitudinal maternal anthropometry.
  • To incorporate maternal information from the last menstrual period, accounting for its measurement error.
  • To propose methods for validating predictions when gold-standard measurements have errors.

Main Methods:

  • Development of a shared random parameter model for GA estimation.
  • Utilizing longitudinal maternal anthropometry and last menstrual period data.
  • Evaluation through simulation studies using a training-test set paradigm.
  • Methodology for prediction validation with error-prone gold-standard measurements.

Main Results:

  • The proposed shared random parameter model effectively estimates gestational age from maternal anthropometry.
  • Simulation studies demonstrated the model's performance under various conditions.
  • The validation methodology proved effective for assessing prediction accuracy with measurement error.

Conclusions:

  • The developed model provides a viable approach for estimating gestational age in resource-limited environments.
  • This methodology can improve pediatric care by enabling more accurate GA assessment.
  • The study offers tools for robust prediction validation in the presence of data imperfections.

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