Table 3:

Rates of breast cancer before and after the start of the mammography screening program, by screening state

Age, yr	1970–1979			2005–2009
				First screens			Active screening			Nonactive screening
	Years-at-risk (1000s)	Rate of invasive cancer per 1000	Rate of DCIS per 1000	No. of patients screened (1000s)	Rate of invasive cancer per 1000	Rate of DCIS per 1000	Years-at-risk (1000s)	Rate of invasive cancer per 1000	Rate of DCIS per 1000	Years-at-risk (1000s)	Rate of invasive cancer per 1000	Rate of DCIS per 1000
40–44	655	1.1	0.08	88.8	1.5*	0.89*	243	1.1	0.28	614	1.0	0.11
45–49	655	1.7	0.08	44.5	2.8	1.17	446	1.6	0.44	454	1.4	0.18
50–54	652	2.1	0.10	29.1	4.7	1.55	503	1.8	0.48	339	1.7	0.17
55–59	598	2.3	0.07	14.3	5.4	0.98	468	2.3	0.54	277	2.0	0.15
60–64	523	2.6	0.07	9.6	8.3	2.61	376	3.0	0.69	217	2.5	0.18
65–69	421	2.7	0.08	6.3	11.2	1.43	286	3.5	0.74	169	2.9	0.27
70–74	319	2.9	0.08	3.3	14.1	1.80	224	3.8	0.74	150	3.1	0.25
75–79	240	2.9	0.12	1.7	16.0	1.72	172	4.0	0.81	153	3.3	0.29
80–84	164	3.2	0.12	0.3	14.5	2.90	127	3.0	0.25	138	3.8	0.17
85–89	92	3.4	0.08	0.1	0.0	0.0	72	2.9	0.10	99	4.2	0.09
Cumulative rate		124	4					137†	26†		130	9
95% CI		121 to 127	3 to 5					133 to 141	25 to 28		126 to 134	8 to 10

Note: CI = confidence interval, DCIS = ductal carcinoma in situ.

^*Used to estimate the detection rate of first screens at age 40 years.

^†Includes detection rate of first screens at age 40 years, given by the detection rate at age 40–44 years.