Table 3.

Parameter estimates for the linear growth model of the mean daily step count per intervention quartile as a function of group assignment.

Effect		Estimate SE	SE	P value	95% CI
Fixed
	Intercept	6473.46	324.26	<.001	5837.91 to 7109.01
	Time	–107.41	96.06	.27	–295.69 to 80.87
	Group	–885.80	466.38	.06	–1799.90 to 28.30
	Days of valid wear	–287.14	227.86	.21	–733.75 to 159.47
	Group by time	322.08	136.77	.02	54.01 to 590.15
Random at level 2 (between persons)a
	Intercept	2,648,712	628,223	<.001	1,417,395 to 3,880,029
	Slope for time	1284	21,090	.48	–40,052 to 42,620
Random at level 1 (within person)b
	Residual	1,399,430	207,992	<.001	991,766 to 1,807,094

^aThe correlation between the intercept and slope for time was 0.90.

^bThe autocorrelation was 0.21.