Evidence for Criterion-Related Validity of Pressure-Mediated Reflection Spectroscopy for Approximating Fruit and Vegetable Consumption among Preschool Children

Background: Skin carotenoids are a valid biomarker for approximating fruit and vegetable consumption (FVC). Veggie Meter® (VM®, Longevity Link Corp.) is a pressure-mediated reflection spectroscopy (RS)-based device that allows for noninvasive and rapid assessment of skin-carotenoid score (SCS) in adults and children. Although VM® is established as a valid tool to measure FVC in adults, there is limited research supporting the validity evidence of the VM® to approximate FVC among preschool children. Objective: The current study aims to assess evidence supporting the criterion-related validity of RS-based SCS for approximating FVC among preschool children (3–5-y old). Methods: We collected cross-sectional data from typically developing preschool children (n = 136) attending the Child and Adult Care Food Program-participating family child care home settings (FCCHs) (n = 46) in Nebraska. Research team members collected children's height and weight to calculate body mass index; and measured children's SCS using the VM®. Children's FVC in FCCHs were collected using dietary observation. In addition, parents (n = 89) completed a shortened food frequency questionnaire to report children's FVC at home. Kendall's Tau (τ) correlation tests were conducted to measure the association between children's SCS with FVC in FCCHs and with parent-reported total fruit and vegetable (FV) frequency scores. Results: Children's SCS were significantly correlated with their mean FVC in FCCHs, τ = 0.14 (P = 0.02), total provitamin A carotenoids intake in FCCHs, τ = 0.19 (P < 0.001), and with parent-reported total FV frequency score, τ = 0.16 (P = 0.04). Conclusion: The correlation coefficients in this study are comparable with results from a meta-analysis examining associations between FVC and SCS in 7–10-y-old children (r = 0.20). Thus, evidence suggests that RS offers a potentially valid, objective, and feasible method to assess preschool children's total FVC in multiple settings, especially in conjunction with other dietary assessment tools.