The children in the 2007-12 study group were more overweight than the children in the 1988-94 group, yet parental perceptions of weight "remained relatively unchanged."
The study was conducted by researchers from New York University School of Medicine's NYU Langone Medical Center in New York City, Georgia Southern University in Statesboro and Fudan University in Shanghai, China.
The authors claim their study is the first to investigate parents' perception of their preschool children's weight status over time.
Data from physical examinations and interviews were drawn from the National Health and Nutrition Examination Survey (NHANES), conducted by the Centers for Disease Control and Prevention (CDC). The researchers studied two groups of children aged 2-5 years old in the US over the time periods 1988-94 and 2007-12. Each group totaled more than 3,000 children.
Parents of these children had been asked whether they thought their children were overweight, underweight or just about the right weight.
The study found that, respectively across the two study groups, 97% and 95% of parents of overweight boys considered their child to be about the right weight. For overweight girls, 88% and 93% of parents thought their child was the right weight.
"The results are consistent with past studies in which a considerably high number of parents incorrectly perceived their overweight/obese preschool child as being 'just about the right weight,'" says Dr. Dustin Duncan, lead author of the study and an assistant professor in the Department of Population Health at NYU Langone and Affiliated Faculty Member at NYU's Global Institute of Public Health.
Of particular concern to the authors was that the children in the 2007-12 study group were significantly more overweight than the children in the 1988-94 group, yet the parental perceptions of children's weight "remained relatively unchanged."
Low-income and African-American parents most likely to misperceive weight
The misperception of weight was found to vary across demographics, with more African-American families perceiving their overweight children to be the right weight than parents from other groups. Weight misperception was also found to be stronger among low-income families, with the association becoming less pronounced as family income increased.
"This was especially concerning because African-American and low-income children in the US have the highest rates of obesity," comments Dr. Duncan.
Instead of using growth charts as the standard to assess the weight of their child, the researchers found that parents typically use a less science-based metric - they compare the weight of their child to other children.
"Research examining social comparison theory suggests that individuals evaluate themselves in relation to others, rather than against an absolute scale," Dr. Duncan confirms, who believes that few parents are able to understand either the growth charts or the implications of the data.
As such, the authors believe that ineffective communication between the medical community and parents accounts for "a substantial part" of the ongoing problems with weight misperception.
Parents with more accurate perceptions of their children's weight are more likely to take action to keep their child at a healthy weight, the authors say, so parental recognition of weight problems in their children is an important component of obesity prevention efforts.
"We need effective strategies to encourage clinician discussions with parents about appropriate weight for their child," says Dr. Jian Zhang, senior author of the study and an associate professor of epidemiology at Georgia Southern University. "This will be critical for childhood weight management and obesity prevention."