Table 1:

Demographic and clinical characteristics of FD-ET and Controls

	FD-control (n = 105)	FD-ET (n = 237)	P value
Age (in years)	58.2 ± 10.2 [59.0]	57.2 ± 9.8 [56.0]	0.26 a
Gender [female]	35 (33.3)	168 (70.9)	< 0.001 b
Ethnicity [white]	99 (95.2)	229 (96.6)	0.55 c
Education (in years)	16.6 ± 2.9 [16.0]	16.7 ± 2.5 [16.0]	0.75 a
Current cigarette smoker	0 (0.0)	6 (2.5)	0.19 c
Cumulative Illness Rating Scale Score	3.8 ± 3.7 [3.0]	4.1 ± 3.5 [4.0]	0.22 a
Total tremor score	6.7 ± 3.0 [6.5]	7.9 ± 2.8 [7.5]	<0.001 a
Spiral axis score (Contingency table)			0.014 d
0	87 (82.9)	173 (73.0)
1	11 (10.5)	25 (10.5)
2	5 (4.8)	25 (10.5)
3	2 (1.9)	9 (3.8)
4	0 (0.0)	5 (2.1)
Spiral axis score (as a continuous measure)	0.26 ± 0.64 [0.0] IQR = 0	0.51 ± 0.97 [0.0] IQR = 1	0.03 a

All values are mean ± standard deviation [median] or number (percentage).

IQR = interquartile range.

^aMann-Whitney test.

^bChi-square test.

^cFisher’s Exact test.

^dOrdinal chi-square test.