A comparison of body composition measurements in college students using three assessment devices

Abstract

Dual-energy X-ray absorptiometry (DXA), bioimpedance spectroscopy (BIS), and ultrasound (US) are commonly used to estimate body composition, but each method has limitations.  This study compared the body composition estimations of the three devices in college students.  Ten males (23.7 ± 1.9 years; 171.9 ± 6.7 cm; 81.8 ± 11.4 kg) and twenty females (23.1 ± 1.9 years; 161.8 ± 6.1 cm; 64.9 ± 15.3 kg) volunteered.  Pearson correlation coefficients between the devices were strong.  Body fat percentage estimations for the DXA, BIS, and US were 30.6 ± 9.2, 28.3 ± 9.1, and 22.8 ± 8.1 respectively.  The ANOVA revealed a difference in body composition between the devices and Tukey’s post hoc tests identified that there was a statistically significant difference between the BIS and the US and the US and DXA, but not between the BIS and DXA.  The level of agreement (LOA) was wide between the DXA and US (mean difference 7.8, LOA between 0.23 and 15.4) and between the BIS and US (mean difference 5.4, LOA between -3.4 and 14), but narrower between the BIS and DXA (mean difference 2.4, LOA between -4.2 to 9).  When comparing changes in body composition, it is best to utilize the same device to minimize the error in the reported differences in body composition.  Future studies should compare the body composition estimation from these devices to a more accurate multi-compartment model to help determine their accuracy in college students.