Table 1.

Mean values for sleep parameters from parent report compared to wrist actigraphy, sleep diary, and self-report survey, together with mean (±se) differences

Variable	Parent	Actigraphy			Diary			Survey
	X	X	Diff (±se)	P*	X	Diff (±se)	P*	X	Diff (±se)	P*
School night
Sleep period	8 h 51 m	8 h 06 m†	45 m (2.92)	<0.001	8 h 16 m	35 m (3.13)	<0.001	8 h 10 m	41 m (4.26)	<0.001
Bedtime	10:09 pm	–	–	–	10:28 pm	−18 m (0.04)	<0.001	10:24 pm	−14 m (0.04)	<0.001
Wake time	6:57 am	7:03 am	−6 m (0.04)	ns	7:07 am	−10 m (0.03)	<0.001	6:54 am	−3 m (0.02)	ns
Weekends
Sleep period	10 h 01 m	8 h 29 m†	1 h 32 m (6.17)	<0.001	8 h 41 m	1 h 21 m (6.09)	<0.001	9 h 21 m	40 m (6.72)	<0.001
Bedtime	11:20 pm	–	–	–	11:38 pm	−18 m (0.07)	<0.001	11:54 am	−35 m (0.07)	<0.001
Wake time	9:16 am	8:26 am	51 m (0.09)	<0.001	8:30 am	47 m (0.08)	<0.001	9:22 am	6 m (0.08)	ns

Notes:

^†Actigraphic sleep period was calculated as the time elapsed from sleep onset to sleep offset;

^*bonferroni adjustment used to adjust for multiple comparisons.