Test-Retest Reliability and Convergent Validity of Two Brief Fruit and Vegetable Intake Questionnaires among School-Aged Children

Abstract

Reliable, valid, and easy-to-implement tools are required to assess children’s fruit and vegetable intake as part of behavior change-focused nutrition education programs; however, the availability of such instruments is limited. The purpose of this study was to examine the reproducibility and accuracy of two brief fruit and vegetable intake questionnaires among 8- to 12-year-old children. A total of 109 participants from diverse racial/ethnic groups were recruited from urban afterschool programs. The results of two short questionnaires (food web and plate activity) were reproducible between two repeated measures conducted one week apart. Compared to a reference 24-h dietary recall, the food web questionnaire had acceptable convergent validity for assessing children’s fruit intake (kappa: 0.51; r = 0.53, p < 0.001), but limited validity for assessing children’s vegetable intake (kappa: 0.43; r = 0.33, p < 0.003). Children tended to overestimate intake when visualizing fruit and vegetable consumption via the plate activity questionnaire, indicating that this questionnaire was not a valid tool to assess children’s fruit and vegetable consumption at dinner meals. Children’s report of fruit intake via the food web questionnaire may be a useful indicator of program success in improving fruit intake.