Table 3:

Results of univariate regression of exposure factors as a predictor of heterogeneity in the association between a 10 μg/m³ increase in PM_2.5 and percent change in mortality, per IQR change in exposure factor (n=311)¹

Exposure factors		Beta (5th; 95th %tile)	F-statistic	p-value
Housing characteristics	Median number of rooms in residence, owner occupied	0.258 (0.120; 0.396)	13.41	<0.001
	Duplex homes	0.133 (0.061; 0.204)	13.29	<0.001
	Median number of rooms in residence	0.102 (0.018; 0.186)	5.616	0.018
	Multi-family homes (≥ 2 units in structure)	0.087 (0.009; 0.164)	4.837	0.029
	Homes with 3-4 units in structure	0.107 (0.011; 0.203)	4.773	0.030
	Single family homes	−0.081 (−0.165; 0.003)	3.605	0.059
	Detached single-family homes	−0.081 (−0.167; 0.006)	3.329	0.069
	Median home age	0.08538 (−0.046; 0.217)	1.625	0.203
	Homes with ≥ 5 units in structure	0.052 (−0.039; 0.143)	1.263	0.262
	Median number of rooms in residence, renter occupied	0.034 (−0.053; 0.120)	0.574	0.449
	Attached single-family homes	0.009 (−0.035; 0.053)	0.152	0.697
Commuting	Commuting on public transportation	0.017 (−0.002; 0.035)	3.172	0.076
	Commuting alone	−0.014 (−0.074; 0.045)	0.222	0.638
	Mean commute time	−0.010 (−0.127; 0.108)	0.026	0.872
Household heating	Oil	0.148 (0.094; 0.202)	28.93	<0.001
	Utility gas	−0.412 (−0.619; −0.205)	15.23	<0.001
	Tank gas	−0.107 (−0.391; 0.178)	0.540	0.463
	Electricity	0.073 (−0.143; 0.290)	0.444	0.506
Meteorological factors	1Heating degree days	0.319 (0.144; 0.494)	12.77	<0.001
	2Cooling degree days	−0.188 (−0.367; −0.010)	4.264	0.040
Complete A/C (predicted + empirical) (n=297)	Central A/C	−0.136 (−0.291; 0.018)	2.992	0.085

¹Data could not be predicted for 1 CBSA due to a missing CDD value

²Annual sum of heating degree days (degrees below 65°F)

³Annual sum of cooling degree days (degrees above 65°F)