Table 7.

Adjusted estimates of group–level incidence rates of nephrolithiasis in South Carolina by age and race from 1997 to 2012: Model 6

Model 6: Age Group (yr)	5-yr Change in Kidney Stone Incidence among Whites (95% Confidence Interval)	5-yr Change in Kidney Stone Incidence among Blacks (95% Confidence Interval)	5-yr Change in Kidney Stone Incidence among Other Races (95% Confidence Interval)
<10	1.11 (0.99 to 1.24)	1.23 (0.89 to 1.69)	0.53 (0.15 to 1.93)
10–14	1.21 (1.13 to 1.29)	1.15 (0.89 to 1.50)	0.94 (0.51 to 1.72)
15–19	1.25 (1.20 to 1.28)	1.37 (1.23 to 1.52)	1.70 (1.34 to 2.16)
20–24	1.13 (1.10 to 1.15)	1.30 (1.22 to 1.38)	1.15 (1.02 to 1.31)
25–34	1.05 (1.04 to 1.07)	1.21 (1.16 to 1.26)	1.13 (1.04 to 1.21)
35–44	1.06 (1.05 to 1.07)	1.20 (1.16 to 1.25)	1.26 (1.18 to 1.36)
45–64	0.95 (0.94 to 0.96)	1.05 (1.02 to 1.07)	1.63 (1.52 to 1.73)
≥65	1.06 (1.04 to 1.07)	1.17 (0.83 to 1.65)	2.44 (1.68 to 3.53)

Model 6 included an interaction term between race, age, and year. All models with interactions additionally included each main effect, lower–order interaction terms, and a random intercept for county of residence. Models examining for race effects were adjusted for age and sex.