Table 1.
Characteristic of Study Subjects
| Value | Cases N (%) |
Controls N (%) |
P-value |
|---|---|---|---|
| Mean age | 48.5 | 48.7 | 0.46 |
| Year of birth (mean) | 1953 | 1953 | |
| Place of residence | |||
| Poland | 565 (22.3) | 565 (22.3) | |
| Other Europe | 281 (11.1) | 281 (11.1) | |
| Israel | 101 (4.0) | 101 (4.0) | |
| Quebec | 163 (6.4) | 163 (6.4) | |
| Canada (other than Quebec) | 511 (20.1) | 511 (20.1) | |
| USA | 917 (36.1) | 917 (36.1) | |
| BRCA mutation | |||
| BRCA1 | 1,920 (75.7) | 1,920 (75.7) | |
| BRCA2 | 618 (24.4) | 618 (24.4) | |
| Mean age at menarche | 12.9 | 13.0 | 0.001 |
| Mean number of children | 1.9 | 2.0 | 0.14 |
| Mean age at 1st birth | 24.5 | 24.3 | 0.14 |
| Oral contraceptive (ever) | 1,562 (61.5) | 1566 (61.7) | 0.91 |