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09:36
Assessment of Child Anthropometry in a Large Epidemiologic Study
Published on: February 2, 2017
Within-family variation in obesity
Joseph Price1, Jeffrey Swigert
1Department of Economics, Brigham Young University, 162 FOB, Provo, UT 84602, United States. joe_price@byu.edu
Economics and Human Biology
|May 30, 2012
Summary
Childhood obesity shows significant variation even among siblings. Over half of siblings differ by more than 20 body mass index (BMI) percentiles, highlighting substantial weight differences within families.
Area of Science:
- Pediatrics
- Genetics
- Public Health
Background:
- Childhood obesity is a growing public health concern.
- Understanding the sources of variation in body mass index (BMI) is crucial for effective interventions.
- Sibling comparisons are often used in econometric studies of health behaviors.
Purpose of the Study:
- To quantify the degree of variation in childhood obesity among siblings.
- To assess the impact of genetic and environmental factors on BMI differences within families.
- To inform the application of sibling comparison models in obesity research.
Main Methods:
- Utilized data from the National Longitudinal Survey of Youth 1979 (NLSY79).
- Analyzed body mass index (BMI) percentiles among siblings.
- Included analyses of identical twins to control for genetic similarity.
Main Results:
- Significant differences in BMI percentiles were observed between siblings.
- Over 50% of sibling pairs exhibited a BMI difference exceeding 20 age-specific percentiles.
- Even identical twins showed an average BMI difference of 12 percentiles.
Conclusions:
- Substantial within-family variation in childhood obesity exists.
- Genetic and shared environmental factors do not fully explain BMI differences among siblings.
- The considerable BMI variation necessitates careful consideration when employing sibling comparison methodologies in econometric analyses.
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