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Updated: Jul 16, 2026
06:48
Clinical Anthropometrics and Body Composition from 3-Dimensional Optical Imaging
Published on: June 7, 2024
Body weight distributions for risk assessment.
Kenneth Portier1, J Keith Tolson, Stephen M Roberts
1American Cancer Society, Statistics and Evaluation Center, Atlanta, GA 30329-4251, USA. kenneth.portier@cancer.org
Summary
Accurate body weight data is crucial for risk assessments. This study analyzes U.S. National Health and Nutrition Examination Survey data to reveal non-uniform changes in age- and sex-specific body weight distributions over 24 years.
Area of Science:
- Environmental Health
- Biostatistics
- Public Health
Background:
- Accurate age-specific average body weight estimates are vital for both deterministic and probabilistic risk assessments.
- Understanding body weight distributions is essential for accurate health risk evaluations.
Purpose of the Study:
- To estimate age-specific body weight distributions for U.S. residents using National Health and Nutrition Examination Survey (NHANES) data.
- To analyze distributional changes in age-specific body weight in the United States from 1976-1980 to 1999-2002.
- To demonstrate the application of derived functions for computing body weight distributions in children.
Main Methods:
- Utilized NHANES data from four surveys spanning 24 years.
- Computed weighted mean and standard deviation of natural log-transformed body weights for single-year age groups.
- Employed piece-wise polynomial spline functions and nonparametric age-smoothed trend lines to model age-specific weight patterns.
Main Results:
- Age- and sex-specific average body weight changes over the study period were found to be non-uniform.
- Developed functions to describe and compare body weight distributional changes across different age groups and time periods.
- Demonstrated the utility of these functions for calculating body weight distributions in pediatric populations.
Conclusions:
- The study provides updated, precise age-specific body weight distributions for the U.S. population.
- Non-uniform trends in body weight necessitate the use of detailed distributional data for risk assessment.
- The developed methodologies can inform public health strategies and risk assessment models.
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