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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.
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.
Abstract:
Accurate assessment of gestational age at birth is necessary for optimal pediatric care. In high resource countries, several methods using ultrasound have been proposed to assess gestational age at birth; however, these methods are not easily accessible for low-resource populations. We develop a shared random parameter model for estimating gestational age at birth from longitudinal maternal anthropometry that incorporates additional maternal information from the last menstrual period, a measure of gestational age collected with sizable measurement error. The proposed methodology is evaluated using simulation studies under a training-test set paradigm. In addition, we propose methodology to validate prediction when some measurements of the gold standard are collected with measurement error. We illustrate the proposed methodologies with data from the NICHD Fetal Growth Studies.
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