Table 2.

Correlation coefficients quantifying associations between the three Children’s Chronotype Questionnaire (CCTQ) parent-report measures and dim light melatonin onset time (DLMO) and actigraphic sleep measures (*p<0.05, **p<0.001).

	CCTQ Chronotype Measures
	MSF	ME	CT
DLMO	0.45**	0.26*	0.32*
Bedtime	0.78**	0.54**	0.27*
Sleep Onset Time	0.80**	0.52**	0.33*
Midsleep Time	0.90**	0.53**	0.27*
Wake Time	0.72**	0.34*	0.11
24-h Sleep Duration (h)	−0.03	−0.10	−0.19

Abbreviations: dim light melatonin onset (DLMO); midsleep on free days (MSF); morningness/ eveningness (ME) score; chronotype (CT) score