Table 1 Characteristics of cases and controls whose Cape Cod residences were served by public water supplies.
From: Breast cancer risk and drinking water contaminated by wastewater: a case control study
Characteristic | Cases (n = 824) No. (%) | Controls (n = 745) No. (%) | Adjusted OR (95% CI)a |
|---|---|---|---|
Family history of breast cancerb | |||
   No | 620 (75) | 602 (81) | 1.0 (reference) |
   Yes | 204 (25) | 143 (19) | 1.4 (1.1 – 1.7) |
Age at birth of first child | |||
   Under 30 | 510 (62) | 530 (71) | 1.0 (reference) |
   Nulliparous, or 30+ | 314 (38) | 215 (29) | 1.6 (1.3 – 2.0) |
Prior breast cancer diagnosis | |||
   No | 761 (92) | 680 (91) | 1.0 (reference) |
   Yes | 63 (8) | 65 (9) | 0.8 (0.5 – 1.1) |
Highest grade completed | |||
   Less than high school graduate | 54 (7) | 75 (10) | 0.6 (0.4 – 0.9) |
   High school graduate | 280 (34) | 237 (32) | 1.0 (reference) |
   Some college/vocational | 249 (30) | 221 (30) | 1.0 (0.7 – 1.2) |
   College graduate | 140 (17) | 131 (18) | 0.9 (0.7 = 1.3) |
   Graduate study/degree | 101 (12) | 81 (11) | 1.1 (0.8 – 1.6) |