Alterations in growth and body composition during puberty. IV. Energy intake estimated by the Youth-Adolescent Food-Frequency Questionnaire: validation by the doubly labeled water method

Background: Estimates of energy intake are required for an understanding of growth and disease; however, few methods of energy intake in children have been validated. Objective: Our objective was to validate energy intake estimated by the You th-Adolescent Food-Frequency Questionnaire (YAQ) against the criterion tota l energy expenditure (TEE) by doubly labeled water (DLW). Design: Twenty-three boys and 27 girls (8.6-16.2 y of age) completed the YA Q and TEE measurements in 1 y. Results: Energy intake by the YAQ (10.03 +/- 3.12 MJ) and energy expenditur e by DLW (9.84 +/- 1.79 MJ) were similar (P = 0.91) with large lower (-6.30 MJ) and upper 1(6.67 MJ) +/- 2 SD limits of agreement. When within-subject CVs of repeated measures of the DLW and YAQ methods a,ere used, 25 of the 50 subjects were deemed to have misreported their energy intake. The discre pancy in energy intake (YAQ - TEE) was related to body weight (r = -0.25, P = 0.077) and percent age body fat (r = -0.24, P = 0.09) but not to age (r = -0.07, P = 0.63) or the time between measures. From logistic regression, fatter boys were more likely to underreport energy intake than were fatter girls. Conclusion: The YAQ provides an accurate estimation of mean energy intake f or a group but not for an individual.