Table 2.

Description of kinematic parameters to describe performance in the nine movement tasks.

Tasks	Parameters	Unit	Description
POCO, POCO-T, SLS	DR pitch	°	Range of sway movement in anterio-posterior direction
	DR roll	°	Range of sway movement in medio-lateral direction
	MSV 3D	°/s	Mean sway velocity in 3-dimensional space
SLW, SCSW	Speed	m/s	Walking speed
	Mov X	cm	Standard deviation of movements in mediolateral direction
	Mov Y	cm	Standard deviation of movements in vertical direction
SIP, pSIP	Knee Amplitude	m	Antero-posterior range of motion of knees
	Amplitude Asymmetry	%	Logarithmic ratio between the knee amplitudes of the larger side to the smaller side
	Cadence	Steps/min	Steps per minute
	Arrhythmicity	%	Positive ratio between standard deviation and average of the step time for one body side
JJ	Hand Cycle Time	s	Time of Hand movement cycle (from maximal hand distance over minimal hand distance to next maximal hand distance)
	Hand Cycle Arrhythmicity	%	Absolute ratio between standard deviation and average of the hand cycle time
	Feet Cycle Time	s	Time of Feet movement cycle (from maximal feet distance over minimal feet distance to next maximal feet distance)
	Feet Cycle Arrhythmictiy	%	Absolute ratio between standard deviation and average of the feet cycle time
FTT	R, L Frequency	Hz	Main tapping frequency (taps per second)

POCO = postural control stance, POCO-T = postural control tandem stance, SLS = single leg stance, SLW = line walk, SCSW = walk at a subjectively comfortable speed, SIP = stepping in place, pSIP = paced stepping in place, JJ = jumping jack, FTT = finger tapping test, DR = deflection range, MSV 3D = mean sway velocity in 3D, Mov X = movement deviation in mediolateral direction, Mov Y = movement deviation in anteroposterior direction at hip level, R = right, L = left, Hz = Hertz.