Table 1.

Components of each factor in the HVI.

Factor	Main componentsa
1 Social/environmental	Percentage of population below the poverty line
	Percentage of population of a race other than white
	Percentage of population with less than a high school diploma
	Percentage of nongreen space
2 Social isolation	Percentage of population that live alone
	Percentage of population > 65 years of age that live alone
3 Air conditioning prevalence	Percentage of homes without central air conditioning
	Percentage of homes with no air conditioning of any kind
4 Preexisting health conditions	Percentage of population diagnosed with diabetes
	Percentage of population > 65 years of age
aThe factors were created using principal components analysis. Listed here are the variables that loaded most heavily on each factor. Reid et al. (2009) explained how the factors were created.