Predictors of maternal misclassifications of their offspring's weight status: a longitudinal study

Background: Very little is known about the factors influencing parental misclassifications of a child's weight status. The aim of this study is to examine the predictors of maternal misclassifications of their adolescent offspring's weight status. Methods: A mother–child linked analysis was carried out using 14-year follow-up data from a population-based prospective birth cohort of 2650 children (52% males) who were participants in the Mater-University Study of Pregnancy in Brisbane (Australia) in 1981. Offspring's observed height and weight and maternal perception of offspring weight were reported when they were 14 years old and predictors were prospectively recorded either at first clinical visit of mothers or at 5 or 14 years follow-up. Maternal misclassifications were defined combining observed body mass index (BMI) categories and maternal perceptions of their offspring's weight status. Results: We found that maternal misclassification of child's weight status was common and included misclassifications both to higher and lower weight categories. Forty percent of mothers of overweight children misclassified their child as normal or underweight, more so in males than females. Fifteen percent of mothers of normal weight children misclassified their child as underweight, again more so in males than females. The main independent predictors of maternal misclassifications of child weight status were gender, child dissatisfaction with appearance, shape, size and weight, dieting to lose weight, general health status, maternal BMI and family meals. Gender, child dissatisfaction, dieting and maternal overweight were especially associated with misclassifications of overweight children. Conclusions: This study identified a number of maternal, child and family factors associated with maternal misclassifications of child weight status. Although relevant for clinical practice, further study is needed, however, to evaluate the benefits and harms of promoting increasing parental and child awareness of the child's weight status at a population level