Validation of Two Measures of Fruit and Vegetable Intake in Third-Grade Students

Brief dietary instruments are used to assess fruit and vegetable intakes in adults because they are inexpensive and easy to administer compared other methods. However, use with young children without prior validation may compromise accuracy. Therefore, the purpose of this study was to validate two brief methods to estimate fruit and vegetable intakes among 3rd-grade children. Two brief instruments were used to estimate intake and frequency with 3rd-grade students (n=108) in one school in Minneapolis in 2012/2013. These included a single retrospective question each about usual fruit and usual vegetable intake illustrated with measuring cup pictures to estimate amounts (FVQ) and a food record based on A Day in the Life questionnaire (DILQ) that measures intake frequency. Three 24-hour recalls were conducted using Nutrition Data System for Research, the first on the same day the questionnaires were completed and the remaining several days later. Two weekday and 1 weekend day recalls were collected by trained interviewers. An algorithm derived from NHANES data was used to convert frequencies assessed in the DILQ into amounts. Deattenuated Pearson correlation coefficients were used to compare intakes assessed with the 24-hr recalls and the FVQ and DILQ. Correlations were low between 24-hour recall and FVQ results (0.08 for total vegetable intake, 0.20 for total fruit and vegetable intake). However, fruit consumption was moderately correlated (0.33). Similar results were observed when recall results were compared with DILQ findings. While agreement was low, these instruments may be more useful for measuring fruit than vegetable intake in 3rd-grade students.