Measuring Fat And Sodium Intake Of Middle School Students - Brief Article

Nutrition Research Newsletter, July, 2001

National guidelines to improve the health of American children recommend reducing total fat, saturated fat and sodium in theft diets. As schools and other organizations develop more dietary interventions, there is an increasing need for low-cost methods to evaluate the effectiveness of these programs. Food records and 24-hour recalls do provide the clearest picture of dietary intake but can be quite costly.

Child and Adolescent Trial for Cardiovascular Health (CATCH) was a multi-center trial evaluating the effectiveness of a school health promotion program in reducing cardiovascular disease risk factors in elementary school children. To replace 24-hour recalls, the CATCH research team developed a simple checklist to serve as a measure of students' fat, saturated fat, and sodium intakes. The scoring algorithm chosen for the CATCH Food Checklist (CFC) is one that assigns scores based on both nutrient content and empirical estimates from the calibration analyses. Since there is a need for simpler alternative measures that are practical, feasible, and cost-effective, a group of researchers evaluated the reliability and validity of scores from the CFC as measures of total fat, saturated fat, and sodium intake in middle school students.

A sample of 365 seventh-grade students from eight schools was used for this study. All subjects were assigned to one of three study protocols that varied the order of CFC and 24-hour dietary recall administration. The CFC was administered in the classroom, taking approximately 10 minutes to complete. The 24-hour recall was administered by an interviewer and took approximately 25 to 30 minutes to complete. Reliability of the CFC was measured by the concordance between the morning and afternoon administrations of the checklist in one of the groups of subjects.

The median value of the reliability test for the CFC food items was 0.85, with the convention criterion for substantial agreement being 0.61. Correlations between CFC scores and 24-hour recalls were 0.36 for total fat, 0.36 for saturated fat, and 0.34 for sodium. CFC scores were able to detect important male-female differences in nutrient intake for total fat, saturated fat, and sodium. The highest agreement between CFC and 24-hour recall was for discrete and readily identifiable foods that appear to be easy for the child to remember and easy for the staff to code (i.e., pizza, cold cereal).

The CFC is a reliable and valid tool for measuring fat, saturated fat, and sodium intake in middle school students. Its brevity and ease of administration make the CFC a cost-effective way to measure middle school students' previous day's intake of selected nutrients in school surveys and intervention studies. One limitation is that it is less precise than other measures of dietary recall. However, this is a tradeoff for the other benefits the CFC offers. Further research should include evaluation of the validity and reliability in other populations such as different aged students and different ethnicities.

Kevin W. Smith, Deanna M. Hoelscher, Leslie A. Lytle, et al. Reliability and Validity of the Child and Adolescent Trial for Cardiovascular Health (CATCH) Food Checklist: A Self-report Instrument to Measure Fat and Sodium Intake by Middle School Students, JADA 101(6): 635-642 (June 2001) [Address correspondence to: Kevin W. Smith, MA, Senior Research Scientist, New England Research Institutes, 9 Galen St, Watertown, MA 02472].