Physical activity moderates the association between school start time and sleep duration in a cross-sectional national sample of adolescents

Table 2 Multiple regression results: MVPA as a moderator in the association between SST and sleep duration

Predictor	b	b 95% CI [LL, UL]	sr²	sr² 95% CI [LL, UL]	Fit
(Intercept)	489.77**	[482.70, 496.85]
Sex^a	7.03*	[0.23, 13.84]	0.00	[− 0.00, 0.01]
Race/ethnicity^b	− 8.90*	[− 16.12, − 1.69]	0.00	[− 0.00, 0.01]
Household income^c	− 7.74	[− 16.09, 0.62]	0.00	[− 0.00, 0.01]
School level^d	40.07**	[33.12, 47.02]	0.10	[0.07, 0.13]
Bedroom TV^e	14.18**	[7.25, 21.12]	0.01	[0.00, 0.02]
					R² = 0.126**
					95% CI [0.09, 0.16]
(Intercept)	249.86**	[196.50, 303.23]
Sex^a	6.60*	[0.02, 13.17]	0.00	[− 0.00, 0.01]
Race/ethnicity^b	− 11.12**	[− 18.11, − 4.13]	0.01	[− 0.00, 0.02]
Household income^c	− 6.20	[− 14.29, 1.89]	0.00	[− 0.00, 0.01]
School level^d	23.17**	[14.27, 32.08]	0.02	[0.00, 0.03]
Bedroom TV^e	13.54**	[6.83, 20.25]	0.01	[0.00, 0.02]
SST_min	0.42**	[0.32, 0.52]	0.05	[0.02, 0.07]
MVPA_tot	0.42**	[0.24, 0.61]	0.01	[0.00, 0.03]
					R² = 0.185**
					95% CI [0.14, 0.22]
(Intercept)	497.43**	[490.18, 504.68]
Sex^a	6.72*	[0.15, 13.29]	0.00	[− 0.00, 0.01]
Race/ethnicity^b	− 10.98**	[− 17.96, − 3.99]	0.01	[− 0.00, 0.02]
Household income^c	− 6.02	[− 14.10, 2.05]	0.00	[− 0.00, 0.01]
School level^d	23.52**	[14.62, 32.42]	0.02	[0.00, 0.03]
Bedroom TV^e	13.22**	[6.51, 19.93]	0.01	[− 0.00, 0.02]
cSST	13.26**	[9.94, 16.59]	0.04	[0.02, 0.07]
cMVPA	9.90**	[5.60, 14.20]	0.01	[0.00, 0.03]
cSST*cMVPA	− 3.65*	[− 7.06, − 0.24]	0.00	[− 0.00, 0.01]
					R² = 0.188**
					95% CI [0.14, 0.22]

N = 1132; reflects the final sample used for analysis, after data cleaning
A significant b-weight indicates the semi-partial correlation is also significant. b represents unstandardized regression weights. sr² represents the semi-partial correlation squared. LL and UL indicate the lower and upper limits of a confidence interval, respectively
^*Indicates p < 0.05. ** indicates p < 0.01
^aRef = female
^bRef = Non-Hispanic White Only
^cRef = < $100,000
^dRef = high school
^eRef = yes

ISSN: 2731-4391