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Background: To date, many epidemiologic studies examining associations between obesity and dietary and sedentary/physical activity behaviors have focused on assessing Body Mass Index (BMI) at one point in time. Recent developments in statistical techniques make it possible to study the potential heterogeneity in the development of BMI during childhood by identifying distinct subpopulations characterized by distinct developmental trajectories. Using Latent Class Growth (Mixture) Modelling (LCGMM) techniques we aimed to identify BMI trajectories in childhood and to examine associations between these distinct trajectories and dietary, sedentary and physical activity behaviors.

BackgroundTo date, population based surveys aimed at gaining insight in health related behaviour of children have often used either child self-reports or parent proxy reports. It remains unclear however, if surveys using different sources of information from either parents or children are comparable. In addition, (over)weight status of children can lead to under- and over reporting by parents and children as a result of social desirability bias. We aimed at gaining insight in the level of agreement between parents and child reports regarding aspects of certain dietary, physical activity and sedentary behaviours, and whether there are differences in agreement between parents and child reports in healthy-weight and overweight children.MethodsWeighted kappa was used to determine the level of agreement between child and parent reports on health-related behaviour in 1998 parent-child dyads. We also stratified for weight status of the children. Information on children’s health related behaviours was obtained by parental and children’s questionnaires, and children’s height and weight were measured. Associations between children’s weight status and children reporting less, reporting more and reporting the same amount of health behaviour as their parents were investigated with multinomial logistic regression analysis.ResultsThe Cohen’s kappa coefficients ranged from almost perfect agreement for the variable means of transportation, fair for the variables breakfast consumption and frequency of outside play to slight for the variables duration of outside play, frequency and duration of TV/DVD viewing and family dinner. Overweight children were significantly more likely to report less breakfast consumption (OR = 2.6 (95% CI: 1.3 – 5.1)) and lower frequency of outside play than their parents (OR = 1.8 (95% CI: 1.1 – 2.9)).ConclusionThere can be considerable disagreement between the health related behaviours of children as reported by parents or the children themselves. Based on the present study, it cannot be concluded whether parents’ or children’s reports are more accurate. For future studies, social desirability and recall bias would be best demonstrated in a validation study comparing child and parent self-reports with more objective measures of physical activity and food intake.Electronic supplementary materialThe online version of this article (10.1186/s40359-018-0227-2) contains supplementary material, which is available to authorized users.

Background Healthy sleep duration is essential to health and well-being in childhood and later life. Unfortunately, recent evidence shows a decline in sleep duration among children. Although effective interventions promoting healthy sleep duration require insight into its predictors, data on these factors are scarce. This study therefore investigated (i) which individual (lifestyle), social and cultural factors, and living conditions and (ii) which changes in these factors might be associated with the changes in sleep duration of Dutch primary schoolchildren observed over time. Method Data from the ChecKid study was used, a dynamic cohort study among 4-13-year-old children living in the city of Zwolle, the Netherlands. Associations between changes in sleep duration and individual (lifestyle) factors (i.e., age, sex, physical activity behavior, sugar-sweetened beverage consumption, screen behavior), social and cultural factors (i.e., parental rules, ethnicity), and living conditions (i.e., parental education, presence of screens in the bedroom, household size) were analyzed using multivariable linear regression. Results A total of 1180 children participated, aged 6.6 ± 1.4 years in 2009. Mean sleep duration decreased from 11.4 ± 0.5 h/night in 2009 to 11.0 ± 0.5 h/night in 2012. Older children, boys, children who used screens after dinner, children with greater computer/game console use, and children whose parents had low levels of education had a greater decrease in sleep duration. Conclusions This article reports on one of the first large, longitudinal cohort studies on predictors of child sleep duration. The results of the study can inform future interventions aimed at promoting healthy sleep in primary schoolchildren.

Background Growing evidence suggests that maternal mental health issues are associated with (young) children’s weight outcomes. However, most studies have been limited by cross-sectional designs and have been aimed at (younger) children. The current prospective study focuses on the link between maternal mental health (i.e., psychological stress and depressive symptoms) and adolescents’ zBMI development. Methods The participants in the present study were part of wave 1 and 2 of a longitudinal study on Dutch adolescents’ and their parents’ health behavior. Adolescents (aged 10–14) and their parents were recruited through six secondary schools in the South and the East of the Netherlands. For this study, we only included biological mothers and their adolescent children who participated in both waves, with data on the main measures in both waves, leaving a final sample of 336 biological mother-child dyads. Adolescents height and weight were measured, and both parents and adolescents filled in validated questionnaires on perceived stress and depressive symptoms and answered additional questions concerning domain-specific stress. Regression analyses were performed in R to examine longitudinal links between maternal stress and depressive symptoms at baseline (T1) and adolescents’ BMI standard deviation scores (zBMI) 6 months later (T2), corrected for baseline zBMI and covariates. Results Maternal general perceived stress (β = .20, p = .002) at T1 preceded higher adolescents’ zBMI at T2, after controlling for baseline zBMI and other covariates, whereas maternal depressive symptoms at T1 (β = −.05, p = .44) and other domain-specific stress did not (maternal financial stress, maternal stress at work, maternal stress at home). Additionally, lower educational level among adolescents (β = .16, p = .001) and adolescent depressive symptoms (β = .16, p = .001) was associated with a higher zBMI at T2. Conclusions Results suggest that maternal general stress, but not depressive symptoms, may influence adolescents’ weight development. Our findings warrant future investigation on whether and how general stress among mothers may predict weight increases of their adolescent offspring.