Table 5.

Relationships between the CSHQ and the SDQ, RBQ-2 domains, CARS, and PPVT-C.

	CSHQ subscale
	Bedtime resistance	Sleep anxiety	Sleep duration	Sleep disordered breathing	Parasomnias	Daytime sleepiness	Night wakings	Sleep onset delay	Total score
Emotional symptoms	0.181	0.164	0.223*	0.002	0.191*	0.330***	0.128	0.240*	0.408***
Conduct problems	0.219*	0.104	0.175	−0.152	−0.026	0.054	0.123	0.221*	0.166
Hyperactivity	0.241*	0.425***	−0.061	0.127	0.235*	0.083	0.126	0.201*	0.247**
Peer problems	0.066	0.098	−0.034	−0.037	0.055	−0.108	0.188*	0.159	0.033
Prosocial behavior	−0.020	−0.204*	0.037	−0.258**	−0.057	0.110	−0.127	−0.111	−0.060
Total SDQ score	0.196*	0.312**	0.126	0.033	0.185*	0.128	0.231*	0.350***	0.324***
Repetitive movements	0.193*	0.265**	0.105	0.237*	0.179	0.113	0.235*	0.185*	0.317**
Rigidity	0.614***	0.143	0.054	0.114	0.116	−0.076	0.079	0.182	0.291**
PRI	0.278**	0.171	0.000	0.229*	0.314**	0.166	0.009	0.143	0.334***
Sensory interest	0.315***	0.282**	−0.037	0.159	0.256**	0.172	0.098	−0.007	0.339***
Total RBQ-2 score	0.433***	0.289**	0.070	0.292**	0.244**	0.109	0.167	0.192*	0.431***
CARS	0.196*	0.412***	0.221*	0.211*	0.167	0.185*	0.291**	0.321**	0.393***
PPVT-C	−0.279**	−0.486***	−0.085	−0.118	−0.276**	−0.134	−0.103	−0.187*	−0.349***

Pearson's or Spearman's correlation coefficients were computed for the ASD subgroup.

Spearman's correlations were computed for nonnormally distributed variables (sleep disordered breathing, parasomnias, night wakings and sleep onset delay, conduct problems, repetitive movements and rigidity).

*P < 0.05, **P < 0.01, ***P < 0.001.

CSHQ, Children's Sleep Habits Questionnaire; SDQ, Strengths and Difficulties Questionnaire; PRI, preoccupation with restricted patterns of interests; RBQ-2, Repetitive Behavioral Questionnaire-2; CARS, Childhood Autism Rating Scale; PPVT-C, Peabody Picture Vocabulary Test-Chinese edition.