Table 1. Comparison of WCST results between case group and control group.

	Case group (n=39) mean (sd)	Control group (n=39) mean (sd)	t	p
Total responses	105.8 (23.2)	100.2 (19.1)	0.91	0.129
Total correct responses	59.2 (17.1)	81.0 (11.3)	5.73	0.008
Total errors	46.6 (13.5)	29.1 (10.9)	17.02	<0.001
Perseverative responses	40.6 (15.8)	27.9 (11.3)	4.76	<0.001
Perseverative errors	36.4 (14.3)	19.3 (11.5)	6.87	<0.001
Non-perseverative errors	10.2 (5.6)	9.9 (5.0)	1.08	0.073
Completed categories	1.89 (1.05)	3.15 (1.28)	6. 03	<0.001
Trails to 1st category	24.5 (7.0)	15.0 (6.7)	10.45	<0.001

WCST=Wisconsin Card Sorting Test