Reliability of adolescents' reports of height and weight

The purpose of our study was to compare adolescents' self-reports of height and weight with measured height and weight to assess possible bias in self-report. The study was designed to be a cross-sectional, clinical study in a primary care Adolescent Medicine Clinic in an urban teaching hospital. The subjects were 725 consecutive patients aged 14-20 years (564 females, 161 males) with initial visits during a 2-month period. Our results showed that height was overreported by 0.5 cm and 0.6 cm by females and males, respectively. Weight was underreported by 1.5 and 1.2 kg by females and males, respectively. Differences in height or weight reports were not due to subjects' age. Females and males in the heaviest quartiles of measured weight underreported weight by significantly more than those in lighter quartiles. There were no differences in the accuracy of height or weight reports when subjects were grouped by height quartile. In conclusion, adolescents' self-reports of weight are particularly likely to differ from measured values, and these differences are largest for heavier individuals. This bias in self-report could affect results of clinical and survey research using self-report. The magnitude of such an effect would likely be small.