Table 1.

Distribution of demographic and family history characteristics in cases and controls

Cases (N = 1,628)Controls (N = 674)
n (%)n (%)
Demographics
    Age (years) at reference *
        <45548 (33.7)221 (32.8)
        45+1,080 (66.3)453 (67.2)
        Mean age49.3 (SD 8.6)49.5 (SD 8.6)
    Race *
        White1,145 (70.3)461 (68.4)
        Black483 (29.7)213 (31.6)
    Religion reported as Jewish
        No1,542 (94.7)659 (97.8)
        Yes86 (5.3)15 (2.2)
    Personal history of bilateral breast cancer
        No1,581 (97.1)
        Yes47 (2.9)
Family history of breast cancer *
    None429 (26.4)224 (33.2)
    Any first or second degree860 (52.8)276 (40.9)
        First degree613 (37.7)172 (25.5)
        Second degree only247 (15.2)104 (15.4)
        No first degree, unknown second297 (18.2)159 (23.6)
        Adopted or unknown first degree42 (2.6)15 (2.2)
    Number of relatives with breast cancer *
        One596 (36.6)203 (30.1)
        Two167 (10.3)64 (9.5)
        Three or more97 (6.0)9 (1.3)
    Breast cancer in one or more relatives diagnosed before age 45 *
        Yes201 (12.3)53 (7.9)
        All diagnosed age 45+608 (37.3)206 (30.6)
    Family history of bilateral breast cancer *
        Unilateral only669 (51.9)222 (44.4)
        Bilateral191 (14.8)54 (10.8)
Family history of ovarian cancer
    None877 (53.9)364 (54.0)
    Any first or second degree82 (5.0)32 (4.7)
        First degree37 (2.3)15 (2.2)
        Second degree only45 (2.8)17 (2.5)
        No first degree, unknown second599 (36.8)254 (37.7)
        Adopted or unknown first degree70 (4.3)24 (3.6)
  • NOTE: Proportions in this table reflect the oversampling of younger cases, Black cases, and women with a family history of breast cancer.

  • * Cases and controls were sampled according to race, age, center, and family history of breast cancer.