Table 4.

Predictors of Kidney Cancer Mortality: Multivariate Regression With Centered Variables

Variable	% Change in Kidney Cancer Mortality	P	95% CI
Urologists per 100,000 people
0.1-2.0 v 0	−12.33	.000	−18.43 to −6.23
2.1-4.0 v 0	−13.16	.000	−18.93 to −7.39
4.1-6.0 v 0	−13.73	.000	−19.85 to −7.62
≥ 6.1 v 0	−7.68	.032	−14.68 to −0.67
Incidence: Each percent increase	0.45	.000	0.38 to 0.53
Metropolitan: If county is metropolitan, compared with nonmetropolitan	−12.77	.000	−16.13 to −9.42
Age: Each percentage point increase in percentage of population older than 65 years	−0.79	.000	−1.16 to −0.42
Income: Each $1k increase in median per capita income	−0.73	.000	−0.95 to −0.52
Insurance: Each percentage point increase in percent of population without health insurance	−0.41	.017	−0.74 to −0.07
Reference group: Kidney cancer mortality per 100,000 people in nonmetropolitan county with 0 urologists	6.159	.000	5.811 to 6.508

NOTE. The following variables were dropped from the analysis because they did not meet statistical significance inclusion criteria: Primary care MD density, Health Professional Shortage Area status, hospital bed density, ethnic distribution, unemployment rate, and level of education in county.