Rationale and methods for a randomized controlled trial of a movement-to-music video program for decreasing sedentary time among mother-child pairs

Table 1 Power calculations for the primary outcome of the study

Primary aim: decrease participants’ sedentariness by using movement-to-music video material
Sedentary time (mean 7 h 40 min, α = 0.05)			Intervention: Accelerometer and DVD group		Control: Accelerometer group		Number of participants (mother + child pair) needed per group
Reduction of sedentary time	power	effect size	Mean	SD	Mean	SD
5.4 %	β = 0.80	0.357	435 min	70 min	460 min	70 min	124
5.4 %	β = 0.80	0.385	435 min	65 min	460 min	65 min	107
5.4 %	β = 0.80	0.417	435 min	60 min	460 min	60 min	91
6.5 %	β = 0.80	0.429	430 min	70 min	460 min	70 min	86
6.5 %	β = 0.80	0.462	430 min	65 min	460 min	65 min	74
6.5 %	β = 0.80	0.500	430 min	60 min	460 min	60 min	63

ISSN: 1471-2458