Table 3.

Numbers of interval cancers within one year of screening, numbers of screens and expected annual incidence from 11-year pre-screening trends, by age and period, with the maximum likelihood estimates of λ and S from the interval cancer data.

Age	Period	One-year interval cancers	Number of screens	One-year interval cancer rate	Expected annual incidence	Proportionate interval cancer rate	Estimate of λ (95% CI)	Estimate of S (95% CI)
50–54	1996–2000	46	106,661	0.00043	0.001792	0.24	0.33 (0.26–0.41)	0.88 (0.85–0.91)
	2001–2005	124	225,343	0.00055	0.002077	0.26
	2006–2009	118	206,848	0.00057	0.002372	0.24
55–59	1996–2000	46	85,072	0.00054	0.001998	0.27	0.23 (0.16–0.31)	0.84 (0.81–0.87)
	2001–2005	149	237,884	0.00063	0.002329	0.27
	2006–2009	126	210,214	0.0006	0.002672	0.22
60–64	1996–2000	41	71,624	0.00057	0.002191	0.26	0.43 (0.37–0.51)	0.99 (0.96–1.00)
	2001–2005	85	178,912	0.00048	0.002448	0.20
	2006–2009	98	204,408	0.00048	0.002697	0.18
65–69	1996–2000	27	65,897	0.00041	0.001969	0.21	0.11 (0.01–0.24)	0.75 (0.71–0.79)
	2001–2005	83	132,407	0.00063	0.001970	0.32
	2006–2009	78	131,161	0.00059	0.001968	0.30