Table 1 Characteristics of each variable
Variable | Description |
|---|---|
MeanPos. AP/ML | Mean position of sway, cm |
RMS | Root mean square distance of CoP, cm |
Area | Area of 95% confidence ellipse, cm2 |
Angle | Absolute value of angle between major axis and ML axis, degree |
Flat | Flattening of 95% confidence ellipse |
AreaSW | Mean triangle area enclosed by mean CoP position and two consecutive points, cm2 |
LNGArea | Total path length of CoP trajectory divided by 95% confidence ellipse |
MV | Mean CoP velocity, cm/sec |
MV_SD | Standard deviation of MV |
MV_CV | Coefficient of variation of MV |
AAMV | Average absolute maximal velocity, cm/sec |
MFreq, AP/ML | Mean frequency of a circular motion with a radius equal to mean amplitude, Hz |
RMF, AP/ML | Ratio of mid-frequency component (0.3–1 Hz) to total power value (0–10 Hz), % |
RHF, AP/ML | Ratio of high frequency components (1–3 Hz) to total power value (0–10 Hz), % |
SLPL, AP/ML | Linear regression against 0.15–1 Hz band in PSD log plot |
SLPH, AP/ML | Linear regression against 1–5 Hz band in PSD log plot |
MT3 | Mean time interval between successive peaks on sway density curve at 3-mm radius, sec |
MP3 | Mean peak value on sway density curve at 3-mm radius, sec |
MD3 | Mean distance between in AP-ML plane successive peaks on sway density curve at 3-mm radius, mm |
FD | Fractal dimension of CoP of planar movement |
Ds | Slope of short-time region in SDA |
Dl | Slope of long-time region in SDA |
CriT | Time interval at the intersection of two regression lines on SDA |
CriD | Mean square value at CriT on SDA |