Table 2.

Error measures of IMU-derived arm swing data, compared to optical system-derived data.

		Healthy Adults 2 km/h	Healthy Adults 3 km/h	Healthy Adults 4 km/h	PwP Preferred
Angle RMSe [°]		0.83	0.91	0.72	1.18
Angular velocity RMSe [°/s]		0.03	0.03	0.03	0.16
No. of swings		3885	3788	4103	1762
Amplitude [°]	Systematic error	0.1	0.4	0.5	0.2
	Random error	2.6	2.2	2.7	3.8
	Absolute error	0.9	0.9	1.1	1.1
Peak angular velocity [°/s]	Systematic error	−0.1	−0.1	0.3	−0.3
	Random error	4.2	4.4	5.3	6.8
	Absolute error	1.4	1.6	1.9	2.0

PwP: patients with Parkinson’s disease; RMSe: root mean square error.