OVERVIEW OF BIOELECTRICAL-IMPEDANCE ANALYZERS

Six commercial bioelectrical impedance analyzers were evaluated to det ermine their accuracy as impedance meters, their sensitivity to contac t impedance, and other operating parameters such as maximum current am plitude and test waveform. Over a range of impedances that simulate hu man body impedance, analyzer errors varied from < 1% to nearly 20%. La rger errors were observed when the contact impedance was at the limits of the operating range of the analyzer. Body models, sources of error , and several simple tests that the user can perform are also discusse d.