To assist in the planning of the National Children's Study (NCS), investigators at the NIH Office of Dietary Supplements, NCI and Johns Hopkins University contracted with Westat, a survey research firm, to conduct a comprehensive review of the scientific literature. This work was a collaborative effort of the NIH and Johns Hopkins investigators with Westat nutritionists, and was sponsored by the NCS Program Office. The literature review focused on dietary and supplement intake assessment methodology, as well as methods of assessing food-borne exposure to environmental contaminants in the age groups targeted by the NCS. The specific groups in the target population include pregnant and lactating women, infants (0 to 12 months), toddlers (13 to 24 months), preschoolers (25 months to 5 years), school age children (6 to 12 years), and adolescents (13 to 18 years). Table 1.1 provides a summary of the validation and calibration studies described in the literature review, by population and assessment and reference method.
The objectives of this literature review are to:
- Identify and describe validated instruments for assessing usual food and nutrient intake patterns and/or vitamin-mineral or herbal supplement intake patterns in the target population;
- Identify and describe validated instruments for assessing exposure to environmental contaminants from food in the target population;
- Describe the socioeconomic and ethnic/cultural characteristics of the populations in which the instruments were validated;
- Describe dietary and supplement assessment instruments employed in large epidemiological studies conducted on one or more of the target age groups and discuss the rationale for the instrument selection;
- Identify methodological issues inherent in assessing food intake in pregnant or lactating women, infants, children, and adolescents; and
- Describe the weight of evidence for the various methods, key issues that are unresolved, and additional information needed to resolve key issues.