Table 4. Breast cancer deaths avoided and breast cancer cases overdiagnosed in a cohort of British women followed up from age 40 to 85 years per 10 000 women invited to screening, for selected-screening schedules.
|
Scenario(frequency and age range) |
Breast cancer deaths avoideda
(per 10 000) |
Breast cancer cases overdiagnosedb
(per 10 000) |
Ratio (per case overdiagnosed) |
Incremental life-years gained (per 10 000) |
Incremental life-years gained (per screening round) |
|---|---|---|---|---|---|
| Mean (95% CI) | Mean (95% CI) | Mean (95% CI) | Mean | Mean | |
| Triennial, 50–70 |
41 (39, 44) |
45 (40, 50) |
0.9 (0.8, 1.1) |
476 |
59.5 |
| Triennial, 47–73 |
47 (44, 49) |
58 (53, 63) |
0.8 (0.7, 0.9) |
498 |
49.8 |
| Triennial, 40–73 |
52 (50, 55) |
60 (54, 66) |
0.9 (0.8, 1.0) |
600 |
50.0 |
| Combinationc |
55 (53, 58) |
72 (67, 78) |
0.8 (0.7, 0.9) |
691 |
40.7 |
| Annual, 47–73 |
90 (88, 92) |
80 (75, 85) |
1.1 (1.0, 1.2) |
1021 |
37.8 |
| Annual, 40–73 | 95 (92, 97) | 93 (87, 99) | 1.0 (0.9, 1.1) | 1152 | 33.9 |
Abbreviation: CI=confidence interval.
a
Baseline in the absence of screening: 256 (254–259) deaths per 10 000.
b
Baseline in the absence of screening: 1054 (1050–1058) diagnoses per 10 000.
c
Annual screening from age 40 followed by triennial screening from age 47 to 73.