Validity of the Remote Food Photography Method against Doubly Labeled Water among Minority Preschoolers

OBJECTIVE: To determine the validity of energy intake (EI) estimations made using the Remote Food Photography Method (RFPM) compared to the doubly-labeled water (DLW) method in minority preschool children in a free-living environment. METHODS: Seven days of food intake and spot urine samples excluding first void collections for DLW analysis were obtained on 39 3-to-5 year old Hispanic and African American children. Using an iPhone, caregivers captured before and after pictures of the child’s intake and pictures were wirelessly transmitted to trained raters who estimated portion size using existing visual estimation procedures and energy and macronutrients were calculated. Paired t-test, mean differences and Bland-Altman limits of agreement were performed. RESULTS: The mean EI using the RFPM was 1,191 ± 256 kcal/d and 1,412 ± 220 kcal/d by the DLW method, resulting in a mean underestimate of 222 kcal/d (−15.6%) (p<0.0001) that was consistent regardless of intake. The RFPM underestimated EI by −28.5% in 34 children and overestimated EI by 15.6% in 5 children. CONCLUSIONS: The RFPM underestimated total EI when compared to the DLW method among preschoolers. Further refinement of the RFPM is needed for assessing EI of young children.