Objective: We quantified maternal misclassification of child weight status and examined determinants associated with maternal perceptions of child weight status.
Methods: Data from the Third National Health and Nutrition Examination Survey (1988-1994) were used. The sample included 5500 children (aged 2-11 years) with maternal interview data. Maternal perceptions of children's weight status were compared with measured weights and statures from which body mass index (BMI; weight/stature2; kg/m2) percentiles and z scores were determined. Frequency analyses determined the percentages of mothers considering their child to be "overweight," "underweight," or "about the right weight." Multivariable logistic regression analyses determined predictors of maternal misclassification of overweight children (> or =95th BMI-for-age percentile) and those at risk for overweight (> or =85th to <95th BMI-for-age percentile).
Results: Nearly one third (32.1%) of mothers reported their overweight child as "about the right weight." Younger children and those with lower BMI-for-age z scores had significantly greater odds of maternal underclassification of child overweight status. For children at risk for overweight, 14.0% of mothers reported sons to be "overweight," whereas 29.0% considered daughters to be "overweight." Odds of maternal misclassification of at-risk children as "overweight" were significantly greater for daughters, older children, children with higher BMI-for-age z scores, and children whose mothers had a lower BMI. Race/ethnicity was not a significant predictor in either model.
Conclusions: Nearly one third of mothers misclassify overweight children as being lower than their measured weight status. Mothers are more likely to identify daughters who are at risk of overweight as being "overweight" than they are sons.