Table 4.

Within-dyad relationships between older sibling and younger sibling physical activity and sedentary behaviors by time period

		Younger sibling
		Model: Active minutes		Model: MET-minutes		Model: Sitting minutes		Model: Screen time
		B (SE)	p	B (SE)	p	B (SE)	p	B (SE)	p
Summer	Intercept	735.0 (183.5)	< 0.001	3801.6 (973.4)	< 0.001	913.0 (283.9)	0.002	754.1 (126.0)	< 0.001
	Older sibling
	Active minutes	0.44 (0.14)	0.004
	MET-minutes			0.45 (0.15)	0.003
	Sitting minutes					0.37 (0.19)	0.05
	Screen time minutes							0.19 (0.10)	0.07
	Adjusted R 2	0.09		0.09		0.03		0.03
Fall	Intercept	779.1 (139.1)	< 0.001	4192.3 (702.1)	< 0.001	896.6 (124.0)	< 0.001	529.3 (78.4)	< 0.001
	Older sibling
	Active minutes	0.14 (0.13)	0.28
	MET-minutes			0.13 (0.12)	0.28
	Sitting minutes					0.23 (0.09)	0.01
	Screen time minutes							0.23 (0.08)	0.004
	Adjusted R 2	0.002		0.002		0.07		0.08

Notes: Active minutes were defined as a 7-day total of moderate and vigorous physical activities (MVPA). The Compendium of Metabolic Equivalents (MET) for children was used to calculate MVPA MET-minutes, with moderate physical activity defined as 3–6 metabolic equivalents and vigorous physical activity defined as > 6.0 metabolic equivalents. Sitting minutes were defined as a 7-day total of sedentary activities such as homework or television viewing, and screen time minutes were a subset of sitting minutes that involved the use of media like television viewing or texting