3). In the Flemish FBDG, products within a food group have been categorised blog of sinaling pathways into three groups: food items that are to be preferred — the ‘preference group’ (e.g. fresh fruit), food items that should be consumed with moderation — the ‘moderate group’ (e.g. fruit juice) and food items that should be avoided — the ‘residual group’ (e.g. confectionery, soft drinks, …). Table 2 Contribution from all food groups to energy, fat, fatty acids and cholesterol (n = 696) Table 3 Contribution from all food groups to protein, carbohydrates and water (n = 696) The Ethical Committee of the Ghent University Hospital (Belgium) granted ethical approval for the study. Signed informed consent was obtained from the parents of all the children participating in the Flanders preschool dietary survey.

Statistical analyses Statistical analyses were performed with the Statistical Package for the Social Sciences for Windows version 14 (SPSS Inc., Chicago, IL, USA). The population proportion formula was used to determine the percentage contribution of each of the 57 food groups to the intake of each dietary component. This was done by summing the amount of the component provided by the food for all individuals divided by the total intake of that component from all foods for the entire study population [7,16,17]. Since the average of a small number of days does not adequately reflect an individual’s usual intake, statistical modelling of dietary intakes is needed [18].

In order to correct for day-to-day variability in the 3d EDR, mean and median ‘usual’ intakes of the population and the proportion below or above defined cut-offs were calculated using statistical modelling (the NUSSER method, developed at Drug_discovery Iowa State University) [19,20]. When using consecutive days, at least three days are required to estimate usual dietary intakes by means of the NUSSER method [19,20]. The programme used to calculate usual intakes was the Software for Intake Distribution Estimation (C-side) [21]. The proportion of the variance on nutrient intakes explained by schools and classes was low (< 5%) in the present study, so clustering effects were not addressed during analysis. Because of the high number of non-consumers in some of the detailed food(group)s, adjusted mean intakes could not be calculated for those food(group)s. However, to give an impression of the magnitude of intakes of the different food(group)s in order to help interpreting the contributions, unadjusted mean and median intakes were added to the tables (tables (tables22 and and3).3).