Parental misperception of their child's weight status and how weight underestimation is associated with childhood obesity.

Objectives: Obesity is a major public health concern worldwide. This study aims to investigate the accuracy of parental perception of child's weight and related factors as well as how underestimation is associated with the prevalence of childhood obesity.

Methods: Data from 793 parents and respective children (6-10 years) were collected during the spring of 2013 and 2014. Height and weight were measured and used to calculate body mass index and obesity was classified using the International Obesity Task Force. Parents' perception of child's weight and socio-demographic characteristics were accessed by a questionnaire. Statistical tests were used, controlling for biological and social covariates.

Results: About 33% of parents misperceived their child's weight, of which 93% underestimated it. Different factors were found associated with greater parental underestimation according to children's weight status (ie, younger age) and sex (ie, higher mother's BMI, lower parental education, and household income for girls; living in an urban place for boys). Underestimation among girls, compared to boys, was more associated with socio-economic features of the family. For both sexes, children with excess weight were more likely to be underestimated by their parents. Parents who underestimated their child's weight were 10 to 20 times more likely to have an obese child.

Conclusions: Findings suggest a social desirability bias in parental reports of child weight status. While some parents recognize their child's weight, others may feel embarrassed to discuss the fact that their child is overweight/obese and may feel reluctant in seeking the advice of a health care professional.