School Age Populations Studies - NCS Dietary Assessment Literature Review

See School Age Children Tables and Exhibits

Table 5.2 presents summary data from epidemiologic surveys of at least 100 subjects that collected food and supplement intake data from school age populations. The two most recent US nutrition monitoring surveys, the 1999-2000 National Health and Nutrition Examination Survey (NHANES) and the 1994-96 Continuing Survey of Food Intake of Individuals (CSFII), each included 24HR (24-Hour Recall) interviews to assess food and beverage intake. In both surveys, children younger than 12 years were interviewed with a parent or guardian present. If the child or parent/guardian was not able to provide intake for meals at school or day care, the school or child care provider was contacted by survey staff for information on the menu served. The diet-related questions in NHANES, CSFII and the integrated What We Eat in America-NHANES survey which is currently in the field, are presented in Table 2.5. The integrated What We Eat in America-NHANES includes two 24HR interviews, one in-person and one by telephone, and a propensity questionnaire (100-item NCI DHQ (Diet History Questionnaire) without portion size information) in all children older than 2 years. Supplement use is queried in a separate questionnaire on frequency, dosage, and duration of use of specific products. The rationale for selecting the instruments for the integrated survey as well as the history of past CSFII and NHANES surveys were recently reviewed (9).

The most commonly used dietary assessment method in school age children in the US is the 24HR. The Bogalusa Heart Study (212), the Study of Children's Activity and Nutrition Study (213), the Child and Adolescent Trial for Cardiovascular Health (214), the Dietary Intervention Study in Children (DISC) (164;215), and the School Nutrition Dietary Assessment Study (216) all used 24HR interviews to assess food and nutrient intake.

Estimated or weighed food records were used in 7 of the 25 studies in Table 5.2. It is important to note that use of the food record outside of the US usually involved intensive training and monitoring of subject recording through a series of interviews conducted in the home or by telephone. FFQ (Food Frequency Questionnaire) instruments were used in 6 studies, two of which used versions of the Youth and Adolescent Questionnaire, which is a modification for children and adolescents of the Harvard FFQ for adults.

Most of the studies and surveys presented in Table 5.2 did not include discussion of methods to assess vitamin and mineral supplement intake in the literature cited.