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Within-person variance for adjusting nutrient distribution in epidemiological studies.
Juliana Masami Morimoto1, Dirce Maria Lobo Marchioni, Chester Luiz Galvão Cesar
1Programa de Pós-Graduação em Nutrição em Saúde Pública, Faculdade de Saúde Pública, Universidade de São Paulo, SP, Brasil.
Revista De Saude Publica
|May 10, 2011
Summary
This study presents within-person variance components for accurate nutrient intake analysis in adults and elderly. Adjusting for this variability is crucial to prevent biased dietary data interpretation.
Area of Science:
- Nutritional Science
- Public Health
- Biostatistics
Background:
- Accurate nutrient intake assessment is vital for public health and clinical nutrition.
- Dietary data often exhibit significant within-person variability, necessitating statistical adjustments.
- Previous analyses may have overlooked within-person variance, potentially leading to inaccurate conclusions.
Purpose of the Study:
- To determine the within-person variance component for nutrient distribution in adults and elderly individuals.
- To provide essential data for adjusting nutrient intake distributions in population studies.
- To highlight the importance of accounting for within-person variability in dietary analysis.
Main Methods:
- Utilized data from a 2007 population-based survey in São Paulo, Brazil (n=511).
- Employed the Iowa State University method to calculate within-person variance components.
- Analyzed nutrient intake data from individuals aged 19 years and over.
Main Results:
- Calculated specific within-person variance components for various nutrients.
- Observed significant differences in these components based on gender for certain nutrients.
- Demonstrated the necessity of these components for accurate dietary intake distribution.
Conclusions:
- Within-person variance components are essential for precise nutrient intake distribution adjustments.
- Failure to adjust for within-person variability can lead to biased data analysis and interpretation.
- These findings support improved methodologies in nutritional epidemiology and public health assessments.
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