Table 2.

Associations of sleep quantity and quality with parent-rated optimism, and parent-, and teacher-rated self-esteem, and social competence of the child.

	Total Optimism		Optimism subscale		Pessimism subscale		Self-esteem		Social Competence
Sleep quantity and quality:	β	P	β	P	β	P	β	P	β	P
Sleep Duration
Linear effect	0.08	0.161	0.08	0.206	-0.06	0.309	.04	.515	.06	.309
Non-linear effect	-0.15	0.015	-0.17	0.005	0.04	0.469	-.05	.373	-.10	.096
Average (7.7-9.3 hours) vs.
Short (≤ 7.6 hours)	-0.15	0.014	-0.16	0.009	0.07	0.291	-.05	.444	-.07	.239
Long (≥ 9.4 hours)	0.04	0.537	0.00	0.977	-0.09	0.166	-.02	.720	-.04	.478
Sleep Latency
Linear effect	-0.15	0.010	-0.13	0.024	0.12	0.044	-.11	.060	.04	.515
Short-average (< 32 minutes) vs.
Long (> 32 minutes)	-0.08	0.179	-0.05	0.356	0.08	0.162	-.12	.026	-.03	.620
Sleep Efficiency
Linear effect	0.07	0.265	0.07	0.226	-0.03	0.603	-.01	.892	-.01	.809
Average-high (> 77.4%) vs.
Low (< 77.4%)	-0.05	0.443	-0.09	0.131	-0.04	0.523	.01	.905	.01	.823

Note. Coefficients represent standardized regression coefficients derived from multiple linear regression analyses adjusted for child's sex, age, body mass index, and parental level of education.