Table 2.

Median and interquartile range (IQR) of baseline pre-operative OFF-medication and post-operative ON-stimulation/OFF-medication UPDRS part III subscores for contralateral (C/L) rigidity, bradykinesia and tremor, and their sum total (total UPDRS-III), for the three groups of active contacts located dorsal to STN, within STN and in cZI

	Baseline score, median (IQR)	Post-DBS score, median (IQR)	Individual percent improvement, median (IQR)	p-value
C/L rigidity
Dorsal to STN	4 (1–6)	1 (0–3)	40% (25–100)	0.001
Within STN	5 (3–6)	2 (1–3)	60% (33–83)	<0.001
In cZI	5 (3–6)	2 (0–2)	75% (38–100)	<0.001
Inter-group p-value	0.308		0.529
C/L bradykinesia
Dorsal to STN	9 (4–14)	3 (1–3)	68% (21–79)	0.001
Within STN	11 (7–15)	3 (2–6)	70% (33–82)	<0.001
In cZI	9 (6–15)	3 (2–5)	62% (34–80)	0.001
Inter-group p-value	0.450		0.886
C/L tremor
Dorsal to STN	5 (1–9)	1 (0–2)	75% (8–93)	0.001
Within STN	3 (0–4)	0 (0–1)	100% (50–100)	<0.001
In cZI	0 (0–7)	0 (0–2)	71% (50–91)	0.031
Inter-group p-value	0.066		0.287
C/L total UPDRS-III
Dorsal to STN (n = 18)	17 (12–24)	5 (3–7)	65% (50–74)	<0.001
Within STN (n = 38)	19 (13–24)	6 (4–10)	69% (37–78)	<0.001
In cZI (n = 16)	18 (11–22)	6 (3–9)	72% (51–75)	<0.001
Inter-group p-value	0.810		0.916

Also shown are medians and IQRs of the individual percentage improvement in the scores seen post-operatively. Intra-group pre- and post-operative absolute scores are compared and p-values are shown in the rightmost column (two-tailed Wilcoxon signed-rank test). Pre-operative baseline scores and post-operative individual percentage improvement in scores are compared between groups (inter-group p-values shown; Kruskal–Wallis test) with no significant inter-group differences