Table 3.

Correlations among variables (N = 134).

	PDSS-2 total	PDSS-2 motor|	PDSS-2 Night symptom	PDSS-2 Disturbed sleep
Onset age	−0.12	−0.20*	−0.19*	−0.06
Current age	0.06	−0.07	0.05	0.07
Disease duration	0.33**	0.27**	0.26**	0.25**
MMSE	0.05	0.01	−0.03	−0.07
UPDRS total	0.44**	0.38**	0.45**	0.40**
UPDRS Part I	0.17	0.15	0.17*	0.21*
UPDRS Part II	0.47**	0.43**	0.47**	0.42
UPDRS Part III	0.27**	0.23**	0.28**	0.21*
UPDRS Part IV	0.40**	0.40**	0.44**	0.43**
BDI	0.39**	0.25**	0.40**	0.47**
BAI	0.44**	0.39**	0.41**	0.34**
H&Y	0.38**	0.25**	0.22*	0.25**
PDQ-39	0.53**	0.41**	0.52**	0.47**
PDSS-2	–	0.69**	0.69**	0.68**
LEDD total	0.41**	0.31**	0.37**	0.38**
Dopamine agonist	−0.01	−0.04	0.13	−0.04

PDSS-2, Parkinson Disease Sleep Scale-2; UPDRS, Unified Parkinson Disease Rating Scale; BDI, Beck Depression Inventory; BAI, Beck Anxiety Inventory; H&Y, Hoehn and Yahr scale; PDQ-39, 39-item Parkinson Disease Questionnaire; LEDD, Levodopa Equivalent Daily Dosage.

^*p < 0.05,

^**p < 0.01.