Sleep, physical activity and BMI in six to ten-year-old children measured by accelerometry: a cross-sectional study

Table 2 Results from the mixed ANOVA-model and marginal means for age-by-gender-by-weekend interaction

Fixed effects		Sleep onset		Sleep end		TST		Sleep efficiency
		chi2	p	chi2	p	chi2	p	chi2	p
sex		5.2	.022	1.2	.267	21.0	<.001	0.3	.572
age		122.2	<.001	11.3	.010	126.1	<.001	20.9	<.001
weekend		353.2	<.001	295.1	<.001	18.0	<.001	7.1	.008
sex*age		1.5	.677	1.9	.595	0.7	.883	1.3	.725
sex*weekend		0.9	.350	2.1	.146	0.3	.579	3.2	.072
age*weekend		5.9	.117	6.9	.074	7.9	.048	3.3	.352
sexageweekend		5.4	.144	1.6	.651	6.2	.101	2.4	.497
Random effects		*est*	SE	*est*	SE	*est*	SE	*est*	SE
actiwatch (sd)		0.009	0.00	0.0	0.00	0.0	0.00	0.31	0.20
subject (sd)		0.490	0.02	0.36	0.02	0.34	0.01	3.29	0.08
as1 (rho)		0.19	0.01	0.19	0.01	-0.04	0.01	0.11	0.02
Residual (sd)		0.86	0.01	0.77	0.01	0.79	0.01	3.11	0.03
		Sleep onset		Sleep end		TST		Sleep efficiency
Marginal means	*Age*	*Mean*	se	*Mean*	SE	*Mean*	SE	*Mean*	SE
Boys on weekdays	6	21.3	0.06	7.0	0.05	9.8	0.05	84.7	0.35
	7	21.3	0.05	7.0	0.04	9.6	0.04	85.3	0.28
	8	21.6	0.06	7.0	0.05	9.5	0.04	85.7	0.33
	9	21.7	0.05	7.1	0.04	9.3	0.04	86.3	0.27
Boys in weekend	6	21.5	0.08	7.2	0.07	9.7	0.06	84.6	0.39
	7	21.7	0.06	7.2	0.05	9.5	0.05	85.2	0.31
	8	22.1	0.07	7.3	0.06	9.2	0.06	85.8	0.36
	9	22.1	0.06	7.5	0.05	9.3	0.05	86.1	0.30
Girls on weekdays	6	21.1	0.06	7.0	0.05	9.9	0.04	85.3	0.33
	7	21.3	0.05	7.0	0.04	9.7	0.04	85.6	0.29
	8	21.5	0.05	7.0	0.04	9.5	0.04	85.8	0.31
	9	21.6	0.05	7.1	0.04	9.4	0.04	86.3	0.28
Girls in weekend	6	21.5	0.07	7.3	0.06	9.8	0.06	85.1	0.37
	7	21.7	0.06	7.3	0.05	9.6	0.05	84.9	0.32
	8	21.9	0.07	7.4	0.06	9.5	0.05	85.7	0.34
	9	22.0	0.06	7.5	0.05	9.4	0.05	85.9	0.31

Abbreviations: chi2 chi-square test statistic, p p-value, mean estimated marginal mean of groups, SE standard error of estimated marginal mean, sd standard deviation of random effect, rho autoregressive correlation of residuals. Note: weekend is defined as Friday and Saturday, weekdays are Sunday-Thursday. n = 1,160 individuals and 7,164 observations of sleep data.

ISSN: 1479-5868