Evaluation of BMI as an Obesity Index for Korean

The purpose of the present study is to evaluate the validity of the BMI as an indicator of obesity for Koreans. The usefulness of the BMI to represent overweight and obesity was evaluated by measuring the relative validity of sensitivity and specificity, and was compared with the validity of triceps skinfold thickness(mm). To measure the relative validity of the BMI and triceps skinfold thickness, body fat(%) was used as a reference measure of obesity. The study population included 844 participants aged 20-69 years who resided in Kuri City in Kyunggi province. Participants were measured regarding weight, height, triceps skinfold thickness and body fat. The prevalence of obesity for male subjects was 32.0%, 66.2%, and 0.9%, and for female subjects, 17.6%, 56.1%, 12.4% based on the BMI, triceps skinfold thickness, and body fat(%) respectively. The prevalence of obesity was higher based on the BMI or triceps skinfold thickness than body fat measurement. The sensitivity and specificity of the BMI were 33.3% and 67.9% in male subjects and 77.7% and 90.8% in female subjects. Sensitivity of the BMI was lower, and specificity was higher than those of triceps skinfold thickness. In summary, BMI as an indicator of obesity for Korean showed a tendency of overestimation of obesity prevalence. Therefore, there is a need to develop a more reliable obesity index other than the BMI for Koreans.