Proceedings of a Workshop Series

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International Standard Book Number-13: 978-0-309-71579-9
International Standard Book Number-10: 0-309-71579-2
Digital Object Identifier: https://doi.org/10.17226/27481

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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2024. Use of meta-analyses in nutrition research and policy: Proceedings of a workshop series. Washington, DC: The National Academies Press. https://doi.org/10.17226/27481.

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PLANNING COMMITTEE FOR THE WORKSHOP SERIES ON THE USE OF META-ANALYSES IN NUTRITION RESEARCH AND POLICY

KATHERINE L. TUCKER (Chair), University Distinguished Professor of Nutritional Epidemiology in the Department of Biomedical and Nutrition Sciences and Director of the Center for Population Health, University of Massachusetts Lowell

MEI CHUNG, Professor, Gerold J. and Dorothy R. Friedman School of Nutrition Science and Policy, Tufts University

RUSSELL JUDE DE SOUZA, Professor, Department of Health Research Methods, Evidence, and Impact, McMaster University

AMANDA J. MACFARLANE, Founding Director of the Agriculture, Food, and Nutrition Evidence Center and Professor of Nutrition, Texas A&M University

CHIZURU NISHIDA, Head of the Cross-Cutting Unit of Safe, Healthy and Sustainable Diets, Department of Nutrition and Food Safety, World Health Organization (retired); Chair, Cochrane Nutrition Advisory Board (until 2023)

JANET A. TOOZE, Professor, Department of Biostatistics and Data Science, Division of Public Health Sciences, Wake Forest University School of Medicine

Staff

TAKYERA ROBINSON, Associate Program Officer (until November 2023)

ALICE VOROSMARTI, Associate Program Officer (from November 2023)

SAMUEL CRAWFORD, Senior Program Assistant

ANN L. YAKTINE, Director, Food and Nutrition Board

Rapporteurs

MELISSA MAITIN-SHEPARD, MMS Health Strategies, LLC

MARIAN FLAXMAN, Informed Solutions, LLC

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Reviewers

This Proceedings of a Workshop Series was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published proceedings as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the charge. The review comments and draft manuscript remain confidential to protect the integrity of the process.

We thank the following individuals for their review of this proceedings:

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the content of the proceedings nor did they see the final draft before its release. The review of this proceedings was overseen by CELINE HESKEY, Loma Linda University. She was responsible for making certain that an independent examination of this proceedings was carried out in accordance with standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the rapporteurs and the National Academies.

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Contents

ACRONYMS AND ABBREVIATIONS

1 INTRODUCTION

Overview of the Workshop Series

Opening Remarks from Workshop Sponsor

2 PLANNING OF SYSTEMATIC REVIEWS AND META-ANALYSES

Planning for Systematic Reviews and Meta-Analyses

Methods for Reducing the Risk of Bias in Systematic Reviews and Meta-Analyses

Panel Discussion

3 EXPLORING BEST PRACTICES OF CONDUCTING META-ANALYSIS

Best Practices of Meta-Analysis in Nutrition Research

Interpreting the Results of Meta-Analyses and Addressing Heterogeneity

Panel Discussion

4 INTERPRETATION AND APPLICATION OF SYSTEMATIC REVIEWS AND META-ANALYSIS TO EVALUATE THE TOTALITY OF EVIDENCE

From Science to Policy: Evaluating Nutrition Evidence for Informed Decision Making

Nutrition and Policy: Evaluating the Evidence

Panel Discussion

5 CLOSING REMARKS

Takeaways from the Workshop Series

REFERENCES

APPENDIXES

A Workshop Agendas

B Speaker and Moderator Biographies

Boxes, Figures, and Table

BOXES

1-1 Statement of Task

4-1 PICO for Health Canada’s Systematic Review on Whole Grain Intake and Coronary Heart Disease

FIGURES

3-1 An example of a data extraction template

3-2 An example of a funnel plot used to identify publication bias

3-3 An example of a GOSH analysis of an influential study

3-4 Forest plot for a systematic review of low-sodium salt substitutes and diastolic blood pressure

3-5 Equations used in the fixed effects and random effects models

3-6 An example of rating risk of bias through color coding in a forest plot

4-1 A systematic approach to health claims substantiation

4-2 Potential types of bias in nutrition studies

4-3 Quality appraisal tool for intervention studies and quality appraisal tool for prospective observational studies used by Health Canada

4-4 USDA NESR’s process for structuring a systematic review

4-5 A hierarchy of evidence for health claims substantiation used by Health Canada

TABLE

2-1 Limitations in Observational Studies

Acronyms and Abbreviations