Table. Associations of Contextual Variables With County-Level Suicide Rates From 1999 to 2016.

Variables	IRR (95% CI)	P Value
Median age^a	1.004 (1.002-1.006)	<.001
% Non-Hispanic white^a	1.005 (1.004-1.005)	<.001
% Men^a	1.004 (0.999-1.008)	.13
Social fragmentation
Fourth vs first quartile	1.077 (1.050-1.103)	<.001
Third vs first quartile	1.056 (1.035-1.077)	<.001
Second vs first quartile	1.037 (1.020-1.055)	<.001
Social capital
Fourth vs first quartile	0.917 (0.891-0.943)	<.001
Third vs first quartile	0.936 (0.914-0.958)	<.001
Second vs first quartile	0.961 (0.943-0.979)	<.001
Ratio of psychiatrists to residents, per 100 000 residents	0.999 (0.998-1.000)	.05
Ratio of primary care physicians to residents, per 100 000 residents	1.000 (1.000-1.001)	.10
% Without health insurance	1.005 (1.004-1.006)	<.001
% Veterans	1.025 (1.021-1.028)	<.001
Ratio of drinking establishments to residents, per 100 000 residents	1.000 (1.000-1.000)	.52

Abbreviation: IRR, incidence rate ratios.

^{^a}

Control variables were global-mean centered; IRRs reflect 1-unit increase from mean.