Comparison of Multiple Methods of Body Composition Estimation with Military Circumference-Based Equations in Active Duty Service Members: A Cross-Sectional Study

Abstract

Introduction: The Department of Defense circumference-based equations (CBEs) are a field-expedient method to estimate body composition, but often disputed as inaccurate. The purpose of this study was: compare the agreement between CBEs, bioelectrical impedance (BIA), and dual-energy x-ray absorptiometry (DXA) and determine if abdominal circumference (AC) is an effective screening tool to estimate %BF.
Methods: Percent body fat (%BF) was estimated with DXA as the reference standard. Bland-Altman analyses and one-way analysis of variance were used to compare body composition methods. Bivariate regressions were used to analyze if AC was a good predictor of DXA-estimated android fat and %BF.Results: Estimations of %BF were 4.2% and 0.7% lower in CBEs compared to DXA in men and women, and 3.4% and 3.2% lower in BIA compared to DXA in men and women, respectively. AC was highly correlated with %BF determined by DXA in males (R2=0.69, p<0.001) and females (R2=0.56, p<0.001). Conclusions: Compared to DXA, CBEs exhibited lower %BF estimates in males and BIA provided lower %BF in males and females. Given the strong correlation between AC and %BF determined by DXA, AC may be deemed a cost-effective and field expedient screening method of body composition estimation in this population.