Table 6 Observed and Expected Numbers of Breast Cancer per Risk Group
Risk group | N° of women | Observed n° of breast cancer | N°of person-years at risk | Detection rate per 1000 (95%CI) | Expected N° of breast cancer§ | Ratio of Observed to Expected (SIR)® | p |
|---|---|---|---|---|---|---|---|
BRCA1/2 | 48 | 5 | 158 | 31.6 (3.7–53.5) | 0.13 | 2320.3(3.1–83.9) | <0.001 |
High | 674 | 23 | 3356 | 6.9 (1.9–10.6) | 5.18 | 3 4.5 (1.5–8.3) | <0.001 |
Intermediate | 257 | 11 | 1108 | 9.9 (1.3–13.5) | 1.23 | 7.0 (2.0–17.1) | 0.0018 |
Slightly increased | 346 | 5 | 1444 | 3.5 (0.1–6.0) | 1.17 | 2.4 (0.9–8.3) | 0.76 |
Overall | 1325 | 44 | 6066 | 7.3 (2.2–11.1) | 9.03 | 4.9 (1.6–7.6) | <0.001 |