title: Bias in self-reported height and weight in preadolescents.
abstract: OBJECTIVE
  To examine the validity of self-reported height and weight and factors related to misreporting in preadolescents. The accuracy of screening for underweight (thinness), overweight, and obesity using self-reported data was also tested.
  
  
  METHODS
  Self-reported height and weight was administered and then measured in 798 fourth graders age 8 to 11 years. Body mass index (BMI) was calculated from self-reported and measured data and BMI categories were determined using international age- and sex-specific BMI criteria.
  
  
  RESULTS
  Preadolescents overestimated their height by 0.54 ± 5.17 cm and underreported their weight by 0.80 ± 3.09 kg. BMI derived from self-reported data was underestimated by 0.47 ± 1.79 kg/m². Measured BMI category was an important independent predictor of bias in self-reported weight and BMI. Children who were overweight or obese underestimated their weight and BMI to a greater degree compared with normal weight/underweight children. The influence of sociodemographic factors on bias in self-reported values was relatively small. Approximately 15% of children were misclassified in BMI categories when self-reported data were used, especially in the underweight (thinness) and obese category.
  
  
  CONCLUSIONS
  Children age 8 to 11 years were not able to accurately estimate their actual height and weight, leading to erroneous estimating rates of their weight status.
authors.affiliation: Department of Human Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, Katholieke Universiteit Leuven, Belgium. jan.seghers@faber.kuleuven.be
authors.forename: Jan
authors.initials: J
authors.lastname: Seghers
authors.forename: Albrecht L
authors.initials: AL
authors.lastname: Claessens
mesh_terms: D015982:Bias; D001827:Body Height; D001835:Body Weight; D002648:Child; D059026:Diagnostic Self Evaluation; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results