. Author manuscript; available in PMC: 2015 Aug 26.

Published in final edited form as: J Int Neuropsychol Soc. 2015 Jan;21(1):8–21. doi: 10.1017/S1355617714001076

Table 1.

Demographic information for participants

Variable	Control	Low^a	Medium^a	High^a
n	191	186	246	261
% Male	35.60	32.26	33.33	43.68
% Caucasian	100.00	96.79	97.01	97.20
Age	43.11 (11.32)	35.20 (7.45)	40.90 (9.51)	44.09 (9.87)
Education (years)	14.70 (2.69)	14.53 (2.53)	14.54 (2.65)	14.22 (2.71)
CAG repeat length	20.08 (3.53)	40.82 (1.54)	42.21 (2.06)	43.74 (2.73)
UHDRS score^b	2.34 (2.90)	3.06 (3.42)	4.11 (4.19)	6.67 (6.03)
Confidence in motor diagnosis	0.35 (0.55)	0.59 (0.67)	0.72 (0.75)	1.09 (0.94)

Note. CAG = cytosine-adenine-guanine; UHDRS = Unified Huntington’s Disease Rating Scale.

Classification of participants into Low, Medium, and High is based on the CAG-age product (CAP) (see “Method” section). Low: low probability (> 15 years from diagnosis); Medium: medium probability (9–15 years from diagnosis); High: high probability of near-future diagnosis (estimated to be <9 years from diagnosis).

The UHDRS assesses motor functioning. Scores range from 0 to 124, with higher scores reflecting more impairment.