title: Accuracy of self-reported intake of signature foods in a school meal intervention study: comparison between control and intervention period.
abstract: Bias in self-reported dietary intake is important when evaluating the effect of dietary interventions, particularly for intervention foods. However, few have investigated this in children, and none have investigated the reporting accuracy of fish intake in children using biomarkers. In a Danish school meal study, 8- to 11-year-old children (n 834) were served the New Nordic Diet (NND) for lunch. The present study examined the accuracy of self-reported intake of signature foods (berries, cabbage, root vegetables, legumes, herbs, potatoes, wild plants, mushrooms, nuts and fish) characterising the NND. Children, assisted by parents, self-reported their diet in a Web-based Dietary Assessment Software for Children during the intervention and control (packed lunch) periods. The reported fish intake by children was compared with their ranking according to fasting whole-blood EPA and DHA concentration and weight percentage using the Spearman correlations and cross-classification. Direct observation of school lunch intake (n 193) was used to score the accuracy of food-reporting as matches, intrusions, omissions and faults. The reporting of all lunch foods had higher percentage of matches compared with the reporting of signature foods in both periods, and the accuracy was higher during the control period compared with the intervention period. Both Spearman's rank correlations and linear mixed models demonstrated positive associations between EPA+DHA and reported fish intake. The direct observations showed that both reported and real intake of signature foods did increase during the intervention period. In conclusion, the self-reported data represented a true increase in the intake of signature foods and can be used to examine dietary intervention effects.
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Anja
authors.initials: A
authors.lastname: Biltoft-Jensen
authors.affiliation: Department of Nutrition,Exercise and Sports, Faculty of Science, University of Copenhagen,Nørre Allé 51,2200Copenhagen N,Denmark.
authors.forename: Camilla Trab
authors.initials: CT
authors.lastname: Damsgaard
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Rikke
authors.initials: R
authors.lastname: Andersen
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Karin Hess
authors.initials: KH
authors.lastname: Ygil
authors.affiliation: Department of Applied Mathematics and Computer Science,Technical University of Denmark, Richard Petersens Plads,Building 324,2800Kongens Lyngby,Denmark.
authors.forename: Elisabeth Wreford
authors.initials: EW
authors.lastname: Andersen
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Majken
authors.initials: M
authors.lastname: Ege
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Tue
authors.initials: T
authors.lastname: Christensen
authors.affiliation: Department of Nutrition,Exercise and Sports, Faculty of Science, University of Copenhagen,Nørre Allé 51,2200Copenhagen N,Denmark.
authors.forename: Louise Bergmann
authors.initials: LB
authors.lastname: Sørensen
authors.affiliation: Department of Kinesiology,University of Waterloo,200 University Avenue West,Waterloo,ON,CanadaN2L 3G1.
authors.forename: Ken D
authors.initials: KD
authors.lastname: Stark
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Inge
authors.initials: I
authors.lastname: Tetens
authors.affiliation: Division of Nutrition, The National Food Institute, Technical University of Denmark,Mørkhøj Bygade 19,2860Søborg,Denmark.
authors.forename: Anne-Vibeke
authors.initials: AV
authors.lastname: Thorsen
mesh_terms: D015982:Bias; D002648:Child; D003718:Denmark; D004032:Diet; D015930:Diet Records; D005260:Female; D005522:Food Services; D006801:Humans; D062409:Lunch; D008297:Male; D012574:Schools; D057566:Self Report
keywords: Direct observation; Faults; Intrusions; Matches; Omissions; Web-based food diaries; n-3 Fatty acids