Preface

This book presents an extended version of the material for the course on “Statistical methods for Environmental Mixtures and Exposome Research”, which I have been teaching at the Department of Environmental Health, Harvard T.H. Chan School of Public Health (HSPH) since 2018. The course is designed as an introductory class, thus making it realistically impossible to cover all topics and methodologies related to the rapidly expanding field of statistical approaches for high-dimensional exposures and their application in exposome research. As such, the goal of this document is not to comprehensibly summarize the existing literature, but rather to introduce the rational and importance of evaluating environmental exposures as mixtures, to present selected topics within the field, and to provide illustrative examples and critical discussion. The content of the course is designed for students and researchers in environmental health sciences with limited statistical background, and this teaching format has been maintained in this book.

A special thanks to Prof. Brent Coull and Dr. Paige Williams (Department of Biostatistic, HSPH) for sharing their material on Bayesian Kernel Machine Regression and Principal Component Analysis, and to Dr. Stefano Renzetti (University of Brescia) for his comments and sharing his software material on Weighted Quantile Sum.

The R statistical software is used for the practical sessions in the class. Despite some basic level of introduction to the specific packages and code examples are here provided, the reader should refer to online documentations, provided at various links throughout the document, for detailed descriptions of the software.

Minor edits to the sections on cluster analysis, WQS, and quantile G-computation, have been made in December 2023. A larger update, which will include the addition of several topics in Chapters 5 and 6, will occur in later 2024.

About the Author

Andrea Bellavia, PhD

Webpage: andreabellavia.github.io. Twitter: andreabellavia

The author takes full responsibility for the content of this book. Permission was obtained for all figures and tables from published papers that are included.

Copyright 2023 Andrea Bellavia
All rights reserved.

Cover art by Maria Bellavia