Validity of self-reported lunch recalls in Swedish school children aged 6-8 years

Previous studies have suggested that young children are inaccurate reporters of dietary intake. The purpose of this study was to validate a single recall of the previous day's school lunch reported by 6-8 year old Swedish children and to assess teacher-recorded intake of the same meal in a standardized food journal. An additional research question was whether parents could report their child's intake of the previous day's lunch. Subjects constituted a convenience sample from the large, multi-country study Identification and prevention of Dietary- and lifestyle-induced health EFfects In Children and infantS (IDEFICS). Validations of both children's recalls and teachers' records were made by comparing results with the duplicate plate reference method.

Twenty-five children (12 boys/13 girls) aged 6-8 years participated in the validation study at one school in western Sweden. Children were accurate self-reporters of their dietary intake at lunch, with no significant difference between reported and weighed intake (Mean difference (SD): 7(50) kcals, p=0.49). Teachers significantly over-reported intake (Mean difference (SD): 65(79) kcals, p=0.01). For both methods, child-reported and teacher-recorded, correlations with weighed intake were strong (Pearson's correlations r=0.92, p<0.001 and r=0.83, p<0.001 respectively). Bland-Altman plots showed strong agreement between child-reported and weighed intakes but confirmed systematic differences between teacher-records and weighed intakes. Foods were recalled by children with a food-match rate of 90%. In all cases parents themselves were unable to report on quantities consumed and only four of 25 children had parents with knowledge regarding food items consumed.

Children 6-8 years of age accurately recalled their school lunch intake for one occasion while teachers recorded with less accuracy. Our findings suggest that children as young as six years of age may be better able to report on their dietary intake than previously suggested, at least for one main meal at school. Teacher-recorded intake provides a satisfactory estimate but with greater systematic deviation from the weighed intake. Parents were not able to report on their children's school lunches consumed on the previous day.