Bioelectrical impedance analysis
Bioelectrical impedance analysis is a technique used in medicine to evaluate the reactance and resistance of a patient's tissues (especially in chronic conditions such as cancer, liver cirrhosis, HIV infection, and in the course of dialysis). When a current is applied to a biological specimen, reactance causes the current to lag behind the voltage, creating a phase shift. When quantified geometrically, this shift is termed a phase angle.
The phase angle reflects the relative contributions of body fluids (resistance) and cell membranes (reactance) of the human body.
- Gupta D, Lammersfeld CA, Burrows JL, et al (December 2004). "Bioelectrical impedance phase angle in clinical practice: implications for prognosis in advanced colorectal cancer". Am. J. Clin. Nutr. 80 (6): 1634–8. PMID 15585779.