TABLE 2—

Negative Binomial Regression Estimates of Colorectal Cancer Mortality Rate Ratios: United States, 1968–2005

Individual or Study Variable	Mortality Rate Ratio (95% CI)
Age group, y
35–44 (Ref)	1.00
45–54	3.97 (3.91, 4.03)
55–64	11.99 (11.79, 12.19)
65–74	27.40 (26.89, 27.91)
75–84	52.82 (51.81, 53.85)
≥ 85	90.27 (88.56, 92.02)
Urbanicity	1.03 (0.99, 1.08)
Black	1.22 (1.20, 1.24)
Male	1.37 (1.37, 1.38)
Time period
1968–1970 (Ref)	1.00
1971–1975	0.98 (0.97, 0.99)
1976–1980	0.98 (0.97, 1.00)
1981–1985	0.95 (0.93, 0.97)
1986–1990	0.92 (0.90, 0.94)
1991–1995	0.88 (0.86, 0.90)
1996–2000	0.82 (0.80, 0.85)
2001–2005	0.75 (0.72, 0.77)
SES	1.14 (1.12, 1.16)
SES × time period
1968–1970 (Ref)	1.00
1971–1975	0.99 (0.98, 1.00)
1976–1980	0.98 (0.97, 0.99)
1981–1985	0.96 (0.95, 0.97)
1986–1990	0.93 (0.92, 0.94)
1991–1995	0.89 (0.88, 0.90)
1996–2000	0.87 (0.86, 0.88)
2001–2005	0.84 (0.83, 0.86)

Note. CI = confidence interval; SES = socioeconomic status.