Using built environment characteristics to predict walking for exercise

Table 6 Geographic variation in physical activity and the built environment

	ZIP code	Census tract	Census block group
	ICC (95% CI)	ICC (95% CI)	ICC (95% CI)
Walking for exercise
Some versus none	0.003 (0.000, 0.025)	0.000 (0.000, 0.051)	0.000 (0.000, 0.102)
Minutes per week^ab	0.000 (0.000, 0.036)	0.046 (0.000, 0.129)	0.055 (0.000, 0.211)
Built environment characteristics
Residential density of 1-km buffer^a	0.739 (0.680, 0.799)	0.920 (0.907, 0.932)	0.953 (0.946, 0.960)
Connectivity of 1-km buffer^a	0.784 (0.731, 0.836)	0.879 (0.861, 0.897)	0.931 (0.920, 0.941)
Park area within 1-km buffer^a	0.330 (0.255, 0.405)	0.601 (0.554, 0.648)	0.778 (0.746, 0.809)

Notes: ICC indicates intra-class correlation coefficient; CI indicates confidence interval; except where otherwise indicated N = 1,608
^a Log-transformed to approximate normality
^b Among participants reporting some walking for exercise: N = 1,000

ISSN: 1476-072X