Analysis of Body Composition Methods in a Community Sample of African American Women

The purposes of the authors in this study were: (1) to determine whether published body mass index and bioelectrical impedance analysis equations agreed with dual energy x-ray absorptiometry body fat percentage measures and (2) to estimate new body mass index and bioelectrical impedance analysis equations in a sample of African American women. Linear regression was used to determine how well 10 body mass index and bioelectrical impedance analysis equations reflected dual energy x-ray absorptiometry body fat percentage measures in this sample of 74 African American women; new body mass index and bioelectrical impedance analysis equations were created using dual energy x-ray absorptiometry body fat percentage measures as the dependent variable. Participants (M = 47.6 years, SD = 7.7) were classified as overweight or obese (BMI Mean BF% = 35.4, SD = 8.2; BIA Mean BF% = 43.3, SD = 6.9; DXA Mean BF% = 41.5, SD = 6.1). R² and SEE values indicated that all body mass index and bioelectrical impedance analysis equations were a poorer fit with less precision, and the new bioelectrical impedance analysis equation discussed in this article was a better fit and was more precise. All 10 body mass index and bioelectrical analysis equations inaccurately estimated dual energy x-ray absorptiometry body fat percentage measures in our sample. The new body mass index equation discussed in this article had less estimation bias and more precision than the published body mass index equations and may be a more accurate equation in African American women.