interpreting test results
BIA 450 support
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effects of patient test position on results

Impedance Test Position - Lying Down
To ensure accurate results an impedance test should be conducted using the following test protocol:

1. Patient should be lying down facing up.
2. Patient should relax and be as still as possible with hands at least 6 inches from the body so that the upper inner arms are not touching the torso, palms facing down.
3. Patient's feet should be at least 8 to 12 inches apart so that the legs are not touching at the thighs.
4. Patient's right ankle and wrist are exposed. Nylon hosiery should be removed.

The regression equations used in the analyzer to calculate fat mass were developed using the above test position. Deviations from this position may change the normal path followed by the test current as it flows through the patient's body. Bioimpedance tests conducted with the patient's arms on the chest or with legs crossed or too close together may lead to slightly lower body fat results.

Standing vs. Sitting Test Position
If room is not available to test patients lying down, then impedance testing can be done with the patient standing or sitting.

If tested while standing or seated the patient's resistance will average approximately 10 to 20 ohms less than while lying down. This difference results in slightly lower body fat readings of approximately 0.5 to 1.0%.

If you are testing patients standing or seated, the standing position should be your first choice. For patients who cannot stand, test them in the seated position.

Note: When testing standing or sitting patients, maintain the basic test procedure with the patient's legs spread shoulder-width apart and arms held away from the body 6 - 10 inches.
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