Table 2.

Accelerometer and GPS sampling characteristics of the 208 participants included in the analysis by community design group^a.

	Conventional (n=143) mean (range)	Smart Growth (n=65) mean (range)	P-valueb
Number of days	7.90 (6.00 – 8.00)	7.90 (7.00 – 8.00)	0.26
% missing accelerometer datac	0.91 (0 – 24.20)	1.46 (0 – 21.01)	0.01
% missing GPS data	29.93 (2.51 – 77.54)	39.90 (7.52 – 76.60)	< 0.001
% accelerometer outliersd	< 0.01 (0 – 0.03)	0.29 (0 – 18.73)	0.80
% GPS outlierse	< 0.01 (0 – 0.000084)	< 0.01 (0 – 0.000081)	0.79
% accelerometer non-wearf	38.02 (18.20 – 75.54)	37.43 (6.92 – 64.00)	0.73
% motorizedg	1.96 (0 – 5.53)	2.34 (0.03 – 4.86)	0.04

^aSummary statistics describe data collected during the sampling period 5am –11pm, excluding school hours on weekdays 9am – 2pm during the school season August 31 - June 10.

^bANOVA and Kruskal-Wallis tests applied for assessing differences between groups.

^cThe mean values in this table represent the means for “ % of 30-second epochs for each subject”.

^dAccelerometer records with greater than 16,383 counts per 30-second epoch.

^eGPS records with speeds greater than 169kph (105mph).

^fAccelerometer records comprising at least 60 minutes of consecutive zero activity counts.

^gGPS records with speeds greater than 32kph (20mph).