Table 2. Correlation between CCI score and neuropsychological performance.

Variables	Pearson's correlation		Model 1		Model 2
	r	p	r	p	r	p
Age	0.145	0.022
Age at onset of PD	0.056	0.374
Duration of PD	0.158	0.013
UPDRS motor score	0.142	0.166
LEDD	0.338	0.003
Level of education	−0.084	0.188
K-MMSE score	−0.370	<0.001	−0.270	<0.001	−0.221	0.001
K-MoCA score	−0.339	<0.001	−0.223	<0.001	−0.168	0.008
Forward digit span	−0.220	<0.001	−0.120	0.058	−0.078	0.227
TMT-A score	0.258	<0.001	0.191	0.003	0.150	0.020
K-BNT score	−0.345	<0.001	−0.239	<0.001	−0.205	0.001
Word similarity	−0.164	0.010	−0.011	0.863	0.025	0.693
Copying task of RCFT	−0.386	<0.001	−0.271	<0.001	−0.236	<0.001
Clock copying (CLOX2)	−0.206	0.001	−0.125	0.050	−0.089	0.169
Delayed recall in SVLT	−0.352	<0.001	−0.239	<0.001	−0.179	0.005
Delayed recall in RCFT	−0.345	<0.001	−0.212	0.001	−0.166	0.009
Semantic fluency (animal)	−0.230	<0.001	−0.106	0.095	−0.043	0.507
Clock-drawing test	−0.311	<0.001	−0.253	<0.001	−0.220	0.001
BDI	0.527	<0.001

Model 1: adjusted for BDI score, Model 2: adjusted for BDI score, age, sex, duration of PD, and level of education, r: correlation coefficient.

BDI: Beck Depression Inventory, CCI: Cognitive Complaints Interview, LEDD: levodopa equivalent daily dose, K-BNT: Korean version of the Boston Naming Test, K-MMSE: Korean version of the Mini Mental State Examination, K-MoCA: Korean version of the Montreal Cognitive Assessment, PD: Parkinson's disease, RCFT: Rey-Osterrieth Complex Figure Test, SVLT: Seoul Verbal Learning Test, TMT-A: trail-making test type A.