Table 1 Selected characteristics of subjects
| Â | Breast cancer cases (n = 891) | Breast cancer controls (n = 840) | Â | ||
|---|---|---|---|---|---|
| Â | Mean | SD | Mean | SD | P value |
Age (years) | 63.0 | 6.3 | 63.0 | 6.3 | 0.9045 |
Height (cm) | 164.1 | 5.7 | 163.6 | 5.5 | 0.0766 |
Weight (kg) | 68.9 | 110 | 68.8 | 11.6 | 0.8153 |
Body mass index | 25.6 | 3.9 | 25.6 | 4.1 | 0.8420 |
Age at menarche (years) | 13.6 | 1.4 | 13.6 | 1.5 | 0.6090 |
Age at first birth (years) | 25.4 | 50 | 24.8 | 4.7 | 0.0126 |
Parity | 1.9 | 1.2 | 2.2 | 1.3 | 0.0000 |
Age at menopause (years) | 50.3 | 3.6 | 50.1 | 3.9 | 0.1223 |
HRT (% ever use) | 0.53 | Â | 0.50 | Â | 0.2523 |
Family history (%) | 0.15 | Â | 0.09 | Â | 0.0002 |
Percent density | 16.7 | 14.3 | 14.6 | 14.0 | 0.0017 |