Abstract
Body mass index (BMI)-for-age percentile is the international method used for the evaluation of overweight and underweight in children. While weight-for-height (WFH) score, which is the percentage of standard weight by the height for each sex and age, is commonly used in Japan, with obese children being defined as those whose WFH is more than 120%. In our study, we compared both definitions by the anthropometric data of 270,720 elementary (6 to 11 years) and 225,600 junior high school students (12 to 14 years) based on the Japanese school health examination survey 2000. First, the WFH scores were calculated for tall (mean +2 SD), average and short (mean −2 SD) boys and girls whose weight was obtained from 95th or 5th percentile BMI for the age in every school grade. In both cases, the WFH scores were higher in short than in tall students, meaning that tall students are easily defined as overweight, while short students tend to be evaluated as underweight by using BMI-for-age. Then the BMI-for-age percentiles were calculated for tall, average and short students whose WFHs were 120% and 80%. The BMI-percentile values widely fluctuated in both boys and girls, even though WHF scores were constant. Based on the results of this study, it is that WFH method is more appropriate for evaluation of adiposity among school-age children.
