Correlation between Percentage of Body Fat by BIA and Other Obesity Indices

Kim, Su Jin; Kim, Su Yung

Abstract

PURPOSE
Obesity is becoming a serious health problem in schoolage children and adolescents. There are several parameters to estimate obesity such as body mass index(BMI), skinfold thickness, obesity index and weight for height. Each parameter has some advantages and disadvantages. Bioelectrical impedance analysis(BIA) seems to be a simple, reproducible, objective and cost effective method for fat evaluation. But there are few studies about normal values and effectivenss in children.
METHODS
We measured weight, height, BIA and skinfold thickness(triceps & subscapular) in 1,116 children aged 7-18 years(584 males and 532 females).
RESULTS
There were statistically high correlations between the percentage of body fat(%BF) measured with BIA and Rohrer index(r=0.041), triceps skinfold thickness(r=0.603), obesity index(r=0.576), subscapular skinfold thickness(r=0.561), BMI(r=0.556) in male. In female, the %BF measured with BIA was highly correlated with BMI(r=0.812), triceps skinfold thickness(r=0.774), subscapular skinfold thickness(r=0.752), obesity index(r=0.735), and Rohrer index(r=0.723). The aging tendency of the %BF measured with BIA was as follows. In males, the percentage of body fat increased steadily until 11 years of age, then decreased afterward. In female, the %BF increased abruptly after 12 years of age until 16 years of age, then slightly decreased afterward.
CONCLUSION
Bioelectrical impedance analysis is a useful method of estimating body fat in childhood obesity.