Fig. 4.

Relationship of two newly proposed metrics that quantify quality of upper limb movement. a Relationship of the Jerk Asymmetry Index to compensatory movement scores (rho = − 0.19, p = 0.09). b Relationship of the spectral arc length of the paretic limb to compensatory movement scores (rho = 0.29, p < 0.01). In b, one outlier with a spectral arc length of > − 6 has been omitted from the plot. Both variables are from out-of-clinic time and had a low relationship with the compensatory movement score