Table 6.

Linear regression estimate ($\mathrm{\beta }$) and 95% CI of association of supervised HVI scores with proportion of all-cause deaths occurring on an extreme heat (EH) day, by tract.

	$N$	Tract ($N=308$)
		$\mathrm{\beta }$ (95% CI)	$R^2$
Supervised, based on mortality occurring on EH day
Continuous HVI	—	0.00 (0.00, 0.01)	0.00
Categorical HVI	—	—	0.01
0–2	0	0.00 (Ref)	—
3–5	35	0.46 (0.28, 0.60)	—
6–7	168	0.51 (0.40, 0.60)	—
8–10	100	0.51 (0.39, 0.61)	—
11–12	5	0.38 ($-0.09$, 0.71)	—
Trend $p$-value	0.10

Note: —, no data; CI, confidence interval; EH, extreme heat; HVI, heat vulnerability index; Ref, reference. Categorical cut-points were determined by creating approximately equal interval categories of HVI scores in ArcMap based on the number of census tracts. Test for trend was assessed based on the categorical model’s $F$ statistic.