. Author manuscript; available in PMC: 2015 Sep 15.

Published in final edited form as: J Phys Act Health. 2013 Jan 30;11(2):348–358. doi: 10.1123/jpah.2012-0043

Table 3.

Mixed Model Estimates^a (95% CI) of Sedentary Time (Minutes/Day), Measured by Actical Physical Activity Monitors, by Study Group

	Workbook	Internet	Difference	P-value
Weekly average
Baseline	447.29 (429.45, 465.13)	443.73 (426.55, 460.90)	−3.57 (−28.30, 21.17)	0.776
Week 6	462.23 (443.83, 480.62)	453.90 (435.80, 472.00)	−8.33 (−34.10, 17.44)	0.524
Week 12	460.70 (441.14, 480.26)	457.71 (440.01, 475.40)	−3.00 (−29.34, 23.34)	0.823
Change from baseline
Week 6	14.93 (−1.18, 31.05) P = .069	10.17 (−4.92, 25.26) P = .184	−4.76 (−26.72, 17.19)	0.669
Week 12	13.41 (−3.26, 30.08) P = .114	13.98 (−0.52, 28.48) P = .059	0.57 (−21.39, 22.53)	0.959
Adjusted^b change from baseline
Week 6	6.20 (−11.06, 23.46) P = .479	−0.02 (−16.60, 16.55) P = .998	−6.22 (−27.01, 14.56)	0.556
Week 12	−2.80 (−25.80, 20.20) P = .811	−2.86 (−24.51, 18.79) P = .795	−0.06 (−20.98, 20.86)	0.996

Random family effect included to account for multiple children per family. Kronecker (UN@CS) covariance structure used for repeated measures within an individual (3 time points × up to 6 daily measurements per time point). Covariance matrix estimated separately for each study group. Satterthwaite correction for denominator degrees of freedom.

Adjusted for calendar month, age, sex, and baseline BMI-for-age z score.