Fig. 4.

4-DoF performance over nine months. a–c Subject S6 4-DoF performance was unstable over time and differed from kinematic performance (paired t-test). d–f Subject S8 performance in 4-DoF over a 9-month period is shown. S8 RU showed an improving trend in Time-To-Target (Pearson, p < 0.05). S8 TH performance after 7 months showed significant improvement in Time-To-Target (paired t-test, p < 0.05). Comparisons to the S8 kinematic set were not explicitly drawn. All values are presented as mean with 95% CI