[Self-reported and measured height and weight in adolescents].
OBJECTIVE
The aim of this study was to assess the validity of self-reported height and weight and resulting body-mass-index (BMI) in adolescents, to identify influencing factors and to generate appropriate algorithms for the correction of self-reported values.


METHODS
In the Kiel Obesity Prevention Study (KOPS) height and weight were assessed in 2,706 12- to 17-year-old adolescents by self-report and by measurements. Differences between self-reported and measured values were calculated. Algorithms for correction of self-reported data were generated in a random sample (n=941) and validated in another random sample (n=946).


RESULTS
Overestimation of height and underestimation of weight resulted in a remarkable underestimation of BMI. Girls underestimated BMI more than boys (-0.8±1.0 kg/m² vs. -0.4±1.1 kg/m²; p<0.01), overweight adolescents underestimated more than normal weight adolescents (boys: -1.4±1.4 kg/m² vs. -0.3±0.9 kg/m²; p<0.01; girls:-1.6±1.3 kg/m² vs. -0.7±0.8 kg/m²; p<0.01). Prevalence of overweight and obesity was underestimated by 2.0% and 1.5%, respectively, in boys and by 2.2% and 2.0%, respectively in girls. Differences between self-reported and measured values were influenced by gender and weight status. Correction of self-reported data resulted in approaching the valid overweight prevalence. However, underestimations persisted.


CONCLUSIONS
Self-reported height, weight and BMI calculated from these values are discrepant from measured data and cause underestimation of the prevalence of overweight and obesity in adolescents. Correction of self-reported values is possible. However, valid data can only be assessed by measurements of height and weight.
Landsberg
B
B
Institut für Humanernährung und Lebensmittelkunde, Christian-Albrechts-Universität zu Kiel.
Bastian
I
I
Plachta-Danielzik
S
S
Lange
D
D
Johannsen
M
M
Seiberl
J
J
Müller
M J
MJ
D000293:Adolescent; D000465:Algorithms; D001827:Body Height; D001835:Body Weight; D002648:Child; D059026:Diagnostic Self Evaluation; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires
Schätz- und Messwerte von Größe und Gewicht bei Jugendlichen.