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Statistical Methods Development and Applications to Perinatal Epidemiology

Zhen Chen
  • Zhen Chen, PhD, Senior Investigator, Biostatistics and Bioinformatics Branch, DiPHR
  • Maddy St. Ville, PhD, Postdoctoral Fellow

We develop statistical methodologies that are motivated by Division of Population Health Research (DiPHR) studies.

Machine learning, exposure mixtures, and diagnostic accuracy

In many epidemiological studies, an index might be an efficient and parsimonious way to capture the effect of a group of exposures (exposure mixture). In these cases, my group has been developing Bayesian additive regression tree–based approaches that allow heterogeneity of the effect of an index. We are also exploring machine-learning and artificial-intelligence methods for the purpose of predicting birthweight. Improved prediction of birthweight has important implications for managing delivery of fetuses that are too large and for taking preventive measures for fetuses that are too small. In diagnostic accuracy, we have continued in ROC curve (visualization designed for evaluating the performance of a machine learning classification system) modeling under various constraints.

Additional Funding

  • NICHD Intramural Research Fellowship (IRF) Award (to Maddy St. Ville)

Publications

  1. Yang J, Liu A, Perkins N, Chen Z. Youden index estimation based on group-tested data. Stat Methods Med Res 2025 45-54
  2. Lim Y, Lu R, St. Ville M, Chen Z. Bayesian additive tree ensembles for composite quantile regressions. Stat Comp 2025 in press
  3. Ghosal S, Gleason J, Grantz K, Chen Z. Maternal BMI and diagnostic accuracy of using estimated fetal growth to predict abnormal birthweight: results from NICHD Fetal Growth Studies. Diagnostics (Basel) 2025 15(11):1398

Collaborators

  • Shanshan Zhao, PhD, Biostatistics & Computational Biology Branch, NIEHS, Durham, NC