Table 4.

Correlation coefficient between ESS scores and PDSS subgroup scores.

Subgroups	Correlation coefficient	P-value
Overall quality of night sleep	−0.118	< 0.001*
Sleep onset and maintenance insomnia	−0.073	0.011*
Nocturnal restlessness	−0.080	0.005*
Nocturnal psychosis	−0.175	< 0.001*
Nocturia	−0.122	< 0.001*
Nocturnal motor symptoms	−0.138	< 0.001*
Sleep refreshment	−0.171	< 0.001*
Daytime dozing	−0.536	< 0.001*

^*Statistically significant (p < 0.05).