Assessing Prevalence
and Trends in Obesity
NAVIGATING THE EVIDENCE
Committee on Evaluating Approaches to Assessing
Prevalence and Trends in Obesity
Food and Nutrition Board
Health and Medicine Division
THE NATIONAL ACADEMIES PRESS
Washington, DC
www.nap.edu
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This activity was supported by Grant No. 72377 from the Robert Wood Johnson Foundation. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-44271-8
International Standard Book Number-10: 0-309-44271-0
Digital Object Identifier: 10.17226/23505
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2016. Assessing prevalence and trends in obesity: Navigating the evidence. Washington, DC: The National Academies Press. doi: 10.17226/23505.
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COMMITTEE ON EVALUATING APPROACHES TO ASSESSING PREVALENCE AND TRENDS IN OBESITY
SHARI BARKIN (Chair), Professor of Pediatrics and William K. Warren Foundation Endowed Chair, Department of Pediatrics, Vanderbilt University Medical Center, Nashville, TN
CHERYL A. M. ANDERSON, Associate Professor, Department of Family Medicine and Public Health, University of California, San Diego, La Jolla
LYNN A. BLEWETT, Professor of Health Policy and Director, State Health Access Data Assistance Center (SHADAC), University of Minnesota, School of Public Health, Minneapolis
ELIZABETH GOODMAN, Associate Chief for Community-Based Research, MassGeneral Hospital for Children and Professor of Pediatrics, Harvard Medical School, Boston, MA
ROSS HAMMOND, Senior Fellow, Economic Studies Program and Director, Center on Social Dynamics and Policy, The Brookings Institution, Washington, DC
SANDRA HASSINK, Immediate Past President, American Academy of Pediatrics and Director, American Academy of Pediatrics Institute for Healthy Childhood Weight, Elk Grove Village, IL
AMY H. HERRING, Carol Remmer Angle Distinguished Professor of Children’s Environmental Health, Professor and Associate Chair, Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina at Chapel Hill
GIRIDHAR MALLYA, Director of Policy and Planning, Philadelphia Department of Public Health, Philadelphia, PA (until September 2015)
MICHAEL G. PERRI, Dean, College of Public Health and Health Professions, and the Robert G. Frank Endowed Professor of Clinical and Health Psychology, University of Florida, Gainesville
EDUARDO SANCHEZ, Chief Medical Officer for Prevention, American Heart Association, Dallas, TX
JACKSON P. SEKHOBO, Director, Evaluation, Research and Surveillance Unit, Division of Nutrition, New York State Department of Health, Menands, NY
SHUMEI S. SUN, W. Hans Carter Professor and Chair, Department of Biostatistics, School of Medicine, Virginia Commonwealth University, Richmond (from July 2015)
Consultant
DONALD HEDEKER, Professor of Biostatistics, Department of Public Health Sciences, The University of Chicago, IL
Study Staff
MEGHAN QUIRK, Study Director
JANET MULLIGAN, Senior Program Associate for Research (until January 2016)
ANNA BURY, Research Assistant (from December 2015)
RENEE GETHERS, Senior Program Assistant
ANN L. YAKTINE, Director, Food and Nutrition Board
Reviewers
This report has been 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 institution in making its published report as sound as possible and to ensure that the report meets institutional standards for objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process. We wish to thank the following individuals for their review of this report:
Lawrence D. Brown, University of Pennsylvania
Christina D. Economos, Tufts University
Barbara C. Hansen, University of South Florida
Shiriki Kumanyika, University of Pennsylvania Perelman School of Medicine
Cynthia L. Ogden, Centers for Disease Control and Prevention
Louise Ryan, University of Technology Sydney
David A. Savitz, Brown University
Andrea Sharma, Centers for Disease Control and Prevention
Anna Maria Siega-Riz, University of Virginia
Marion Standish, The California Endowment
Mary T. Story, Duke University
Although the reviewers listed above have provided many constructive comments and suggestions, they were not asked to endorse the conclusions
or recommendations nor did they see the final draft of the report before its release. The review of this report was overseen by Eileen T. Kennedy, Tufts University, and Diane F. Birt, Iowa State University. They were responsible for making certain that an independent examination of this report was carried out in accordance with institutional procedures and that all review comments were carefully considered. Responsibility for the final content of this report rests entirely with the authoring committee and the institution.
Preface
Obesity prevalence and trend estimates are at the crux of informing research, policies, and interventions. Stakeholders at the national, state, regional, local, and community levels search for information relevant to their particular jurisdictions to know how best to proceed. Often times, however, the available estimates appear to provide different accounts of the same issue. Obesity prevalence could be increasing, decreasing, or stabilizing depending on which published report is being considered. Underlying these seemingly conflicting results are not only fundamental principles of epidemiology and statistics, but also methodological approaches specific to the assessment of obesity. The interplay of these factors can make interpretation and application of the results challenging. It is the intent of this consensus report to examine key elements that affect the meaning of an obesity prevalence and trend estimate in order to help those seeking to use the published reports to systematically inform the decisions they need to make.
Prior to my involvement with this consensus study, I thought reviewing published reports was a relatively straightforward process. I relied on my training and experiential knowledge to guide my understanding of the findings. As a researcher who collects height and weight data on preschool-aged children, I was well aware of how difficult it can be to measure a young child, but also how critical it is in accurately assessing obesity status. As a medical doctor who has seen the demographic characteristics of my patient population change over time, I have encountered influxes and effluxes of population groups that exhibit different levels of obesity risk and have recognized that this has direct implications for understanding obesity prevalence and trends in my community. Now at the end of this study, I
am struck by the number of factors the committee identified as having an impact on obesity prevalence and trend estimates.
In preparing this report, the committee was primarily guided by two perspectives. First was the viewpoint of the investigator conducting a study that eventually leads to a published report. Second was the perspective of those at the national, state, and local levels who use reports to inform decision making (hereafter referred to as “end users”). The committee envisioned a range of end users, including but not limited to, policy makers and program planners at government public health agencies or nonprofit organizations; persons working in other public agencies (e.g., transportation, planning, parks and recreation), state legislatures, and educational institutions; private sector foundations and corporations; researchers and other data generators; and health care providers and payers. Given the array of potential end users, each with their own unique information needs and decisions to make, the committee developed a conceptual framework for extracting meaning from published reports that is intended to have broad application. These two perspectives, however, do not operate in isolation, and the committee foresees ways investigators and end users can enhance their collaborations to improve the future of data collection, analysis, and reporting. Advances that are on the horizon, both technological and otherwise, have the potential to encourage these collective efforts.
The committee would like to thank those who made contributions to this report. The Health and Medicine Division study staff included our incredibly hard-working study director, Meghan Quirk; Janet Mulligan; Anna Bury; and Renee Gethers. Their commitment to evidence and high quality was evident in their everyday work. Ann Yaktine, Director of the Food and Nutrition Board, gently guided us all toward our highest standards. The committee would also like to acknowledge the contributions of Lynn Parker, Senior Scholar, who provided critical feedback on the report; Anne Rodgers, who helped to organize and edit the report; Elena OvaittWeiss, who worked with the committee to design the framework; and Claire Wang, who provided feedback during initial framework development.
This report represents the collective efforts of the committee. The diverse perspectives—pediatrics, epidemiology, biostatistics, public health, heath disparities, and beyond—truly enriched this final product. Each member volunteered a substantial amount of time, with schedules that were overbooked and that sometimes took them across the globe and different time zones, to complete this report. The committee’s dedication to and passion for wrapping their minds around the complexities of the topic was apparent throughout this study process. It is one of life’s greatest joys
to work with inspirational, intelligent colleagues who push you to think deeply. I am grateful for their dedication and hard work.
Shari Barkin, Chair
Committee on Evaluating Approaches to Assessing
Prevalence and Trends in Obesity
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