43
VIII. ABOUT RESULTS
Like in standard BIA, results need to be interpreted via comparison with a comparable normal
population. BIVA also uses reference values to place the measurement point created by
resistance/reactance values in context. Reference values are adjusted for age, BMI, gender, and
ethnicity to plot tolerance ellipses onto the graph. The three tolerance ellipses correspond to the
50th, 75th, and 95th percentile of the healthy reference population. Values outside the 95th
percentile in the following four quadrants may indicate the following conditions
17
:
1) Upper right quadrant: Dehydration
2) Upper left quadrant: Good athletic training
3) Bottom left quadrant: Edema
4) Bottom right quadrant: Malnutrition
Whole-body phase angle (50 kHz)
Phase Angle
Phase Angle ( )
o
Age ( years )
95%
50%
5%
8.0
7.0
6.0
5.0
4.0
20
30
40
50
60
70
80
3.0
6.1
o
Whole-body phase angle (50 kHz)
Phase Angle
Phase Angle ( )
o
Age ( years )
95%
50%
5%
7.0
6.0
5.0
4.0
3.0
20
30
40
50
60
70
80
5.6
o
Male
Female
BIA measures impedance (Z), which is comprised of reactance (Xc) (correlating with cell
integrity), and resistance (R) (correlating with the distribution of water within and outside the cell
membrane)
18
.
The angle of the hypotenuse in the triangle drawn using (Z), (Xc), and (R) is the Phase Angle,
which is correlated with factors such as age, gender, malnutrition, inflammation, and BMI. The
MA801 compares the subject's phase angle with their respective population.
17. Data-Input GmbH. The BIA compendium.
18. Data-Input GmbH. The BIA compendium.