Assessing Body Composition for Resource-Limited Settings: Agreement of a Scalable BIA Device Compared to DXA and Clinical BIA in Adults With Obesity

Background Accurate tracking of skeletal muscle mass (SMM) and fat mass percent (FM%) is central to evaluating obesity treatment. The InBody H20N bioelectrical impedance analysis (BIA) device could offer a scalable, lower-cost alternative. However, its accuracy compared to dual-energy X-ray absorptiometry (DXA) and research-grade BIA in adults with obesity is unknown. Methods Baseline SMM and FM% was measured in 55 participants with obesity (62.6±7.6 y, 67.3% female, BMI: 37.6±5.7 kg/m 2 ) enrolled in a behavioral weight-loss program using three modalities: the InBody H20N, InBody S10, and DXA. Agreement was assessed using intraclass correlation coefficients (ICC) analyses with two-way mixed-effects and absolute-agreement, Bland-Altman plots with limits of agreement, and Lin’s concordance correlation coefficients. Results For SMM, agreement was good between H20N and DXA (ICC 0.78; 95% CI -0.15-0.94) and excellent between H20N and S10 (ICC 0.93; 95% CI 0.87–0.96). For FM%, agreement was excellent between H20N and DXA (ICC 0.93; 95% CI 0.79–0.97) and good between H20N and S10 (ICC 0.81; 95% CI 0.66–0.89). All ICCs were statistically significant (p<0.001). Conclusion Results indicate that the H20N provides clinically useful estimates of body composition relative to DXA and research-grade BIA, supporting its potential in resource-constrained environments.