Body Mass Index Accuracy in Preadolescents: Can We Trust Self-Report or Should We Seek Parent Report?

ObjectivesTo assess the accuracy of self- and parent-report of weight, height, and body mass index (BMI) in children between 8 and 12 years of age and to determine whether self- or parent-report should be preferred for preadolescents' subjective measures.Study designThrough at-home questionnaires, 875 preadolescent children (44% boys; 56% girls) and their parents (N = 821) were asked to report the children's weight and height. Objective weight and height were measured at school by trained interviewers.ResultsCorrelations between objective, self-reported, and parent-reported measures were strong for weight, height, and BMI, but children and parents generally underestimated the children's weight by about 1 kg, their height by less than 1 cm, and their BMI by less than 0.25 kg/m2. The magnitude of the underestimation varied by age, sex, and BMI category, with older children, girls, and children in the overweight and obese BMI categories underestimating their weight to a greater extent. Weight estimates provided by girls' parents tended to be lower than the real values more often than those of boys' parents.ConclusionsChildren and parents are likely to misreport children's weight, height, and BMI. For most youths aged 8 years of age and older, self-report appears as accurate as parent-report and could, therefore, be used interchangeably.