Reliability for multiple frequency bioelectric impedance.

Multifrequency impedance may help to quantify body fluid compartments and levels of hydration among individuals. Most studies of bioelectric impedance use impedance machines operating at a frequency of 50 kHz, and observer error is low. The present study evaluates multifrequency impedance measurements at 15 frequencies from 5 to 1,300 kHz to determine observer reliability in 20 White subjects of each sex, 18-65 years of age.