Table 2.

Descriptive statistics and bivariate correlations between variables included in analysis (full sample size: N = 546)

		1.	2.	3.	4.	5.	6.	7.	8.	9.	10.
1.	Bedtime Routine Inconsistency	1.00
2.	Poor Quality Sleep Environment	.07	1.00
3.	Security Positive	−.05	−.16**	1.00
4.	Security Negative	.12**	.07^	−.10*	1.00
5.	Family SES	−.11*	−.26**	.21**	.00	1.00
6.	Sleep Duration	−.09^	−.16**	.11*	−.04	.14*	1.00
7.	Sleep Timing	.22**	.22**	−.21**	.06	−.20**	−.34**	1.00
8.	Sleep Variability	.20**	.18**	−.14**	.14**	−.13**	−.16**	.34**	1.00
9.	Sleep Activity	.01	.11*	−.04	.05	−.11*	−.32**	.05	.26**	1.00
10.	Sleep Latency	.02	.11*	.04	.05	.03	−0.01	.15**	.14**	.16**	1.00
	N	502	539	546	546	536	444†	444†	443†	444†	440†
	M	0.01‡	3.39	0.01‡	0.00‡	48.21	−0.05‡	−0.06‡	0.02‡	0.24‡	39.68
	SD	0.86	1.78	0.01	0.01	13.05	0.84	0.87	0.81	0.91	23.21

Note: Sleep variables, including Sleep Duration, Timing, Variability, and Activity, represent composites of several actigraphic variables. These composites, along with descriptive information about each of the included acitgraphic variables, are described in Table 1.

^{^}p ≤ .10

^*p ≤ .05

^**p ≤ .01 – all two-tailed

^†Smaller number of useable actigraphy cases were due to problems associated with actigraphy data collection, including technical failure of the device and loss/destruction of the actigraph while the family had the device.

^‡Denotes that this variable is either standardized or a standardized composite