Table 1 Characteristics of breast cancer cases and controls.
From: Breast cancer risk associated with different HRT formulations: a register-based case-control study
| Â | Breast cancer N = 3593 | BC controls N = 9098 | ||
|---|---|---|---|---|
Age at diagnosis (mean, SD) | 54.6 | 9.3 | 50.6 | 10.1 |
| Â | N | % | N | % |
Education | Â | Â | Â | Â |
University level | 1066 | 29.7 | 3215 | 35.3 |
Lower education | 2483 | 69.1 | 5817 | 63.9 |
Age at menarche | Â | Â | Â | Â |
< 13 years | 1926 | 53.6 | 4870 | 53.5 |
13 + years | 1583 | 44.1 | 3998 | 43.9 |
Child bearing history | Â | Â | Â | Â |
0–1 child | 1524 | 42.4 | 3358 | 36.9 |
2+ children | 1992 | 55.4 | 5648 | 62.1 |
Age at first live birth | Â | Â | Â | Â |
<= 22 years | 1502 | 41.8 | 3821 | 42.0 |
> 22 years | 1626 | 45.3 | 4276 | 47.0 |
Nulliparous & no live birth | 367 | 10.2 | 840 | 9.2 |
Breast-feeding | Â | Â | Â | Â |
never | 1924 | 53.6 | 3957 | 43.5 |
1 month and more | 1592 | 44.3 | 5047 | 55.5 |
OC use | Â | Â | Â | Â |
never | 1079 | 30.0 | 1805 | 19.8 |
ever | 2508 | 69.8 | 7271 | 79.9 |
HRT use | Â | Â | Â | Â |
never | 2080 | 57.9 | 5910 | 65,0 |
ever | 1513 | 42.1 | 3188 | 35.0 |
Family history of breast cancer | Â | Â | Â | Â |
No | 2453 | 68.3 | 8400 | 92.3 |
Yes | 550 | 15.3 | 649 | 7.1 |
Body mass index | Â | Â | Â | Â |
<25 | 1415 | 39.4 | 4470 | 49.1 |
25 + | 2152 | 59.9 | 4508 | 49.6 |