Comparison Of Withings Bodycardio To Gold Standard Measurements Of Pulse-Wave Velocity And Body Composition

General Wellness Products (GWP) are widely used by consumers, human physiology scientists, and healthcare practitioners. However, current research on GWP accuracy is limited and often reports large inaccuracies. Purpose: The purpose of this study was to assess the Withings BodyCardio for accuracy in the measurement of body composition and arterial health when compared against gold standard laboratory measurements. Methods: Healthy, young males (N=10) and females (N=10) were assessed for measures of body composition and pulse-wave velocity (PWV) in a randomized order utilizing air displacement plethysmography (BodPod), applanation tonometry (SphygmoCor), and the Withings BodyCardio. Measures of body composition and PWV were compared with criterion measures using the Bland-Altman analysis and mean absolute percent error (MAPE). Results: Data is reported as Bias (95% Confidence Interval). The BodyCardio overestimated PWV by 0.68 m/s (-0.16, 1.51) and fat mass by 2.91 kg (-2.91, 8.73). BodyCardio PWV and fat mass estimations had a MAPE of 9.7% and 25.8%, respectively. The BodyCardio underestimated body mass and fat-free mass by 0.11 kg (-0.41, 0.18) and 2.87 kg (-9.04, 3.30), respectively. BodyCardio body mass and fat-free mass estimations had a MAPE of 0.15% and 5.6%, respectively. Discussion: The Withings BodyCardio should be used cautiously for measures of fat mass and fat-free mass, although it provides accurate measures of body mass and PWV.