title: Reproducibility and validity of a diet quality index for children assessed using a FFQ.
abstract: The diet quality index (DQI) for preschool children is a new index developed to reflect compliance with four main food-based dietary guidelines for preschool children in Flanders. The present study investigates: (1) the validity of this index by comparing DQI scores for preschool children with nutrient intakes, both of which were derived from 3 d estimated diet records; (2) the reproducibility of the DQI for preschoolers based on a parentally reported forty-seven-item FFQ DQI, which was repeated after 5 weeks; (3) the relative validity of the FFQ DQI with 3 d record DQI scores as reference. The study sample included 510 and 58 preschoolers (2.5-6.5 years) for validity and reproducibility analyses, respectively. Increasing 3 d record DQI scores were associated with decreasing consumption of added sugars, and increasing intakes of fibre, water, Ca and many micronutrients. Mean FFQ DQI test-retest scores were not significantly different: 72 (sd 11) v. 71 (sd 10) (P = 0.218) out of a maximum of 100. Mean 3 d record DQI score (66 (sd 10)) was significantly lower than mean FFQ DQI (71 (sd 10); P < 0.001). The reproducibility correlation was 0.88. Pearsons correlation (adjusted for within-person variability) between FFQ and 3 d record DQI scores was 0.82. Cross-classification analysis of the FFQ and 3 d record DQI classified 60 % of the subjects in the same category and 3 % in extreme tertiles. Cross-classification of repeated administrations classified 62 % of the subjects in the same category and 3 % in extreme categories. The FFQ-based DQI approach compared well with the 3 d record approach, and it can be used to determine diet quality among preschoolers.
authors.affiliation: Department of Public Health, Ghent University, University Hospital 2BlokA, De Pintelaan 185, 9000 Ghent, Belgium. inge.huybrechts@ugent.be
authors.forename: Inge
authors.initials: I
authors.lastname: Huybrechts
authors.forename: Carine
authors.initials: C
authors.lastname: Vereecken
authors.forename: Dirk
authors.initials: D
authors.lastname: De Bacquer
authors.forename: Stefanie
authors.initials: S
authors.lastname: Vandevijvere
authors.forename: Herman
authors.initials: H
authors.lastname: Van Oyen
authors.forename: Lea
authors.initials: L
authors.lastname: Maes
authors.forename: Erika
authors.initials: E
authors.lastname: Vanhauwaert
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Temme
authors.forename: Guy
authors.initials: G
authors.lastname: De Backer
authors.forename: Stefaan
authors.initials: S
authors.lastname: De Henauw
mesh_terms: D001530:Belgium; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004032:Diet / Q000592:standards*; D004034:Diet Surveys; D017408:Guidelines as Topic; D006801:Humans; D018673:Nutrition Policy; D010290:Parents; D010349:Patient Compliance; D012016:Reference Values; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*