Table 2

Mother’s history of cancer as recorded in the subject’s and mother’s medical records:a Kaiser Permanente Northern California, breast cancer cases and controls, diagnosed with incident breast cancer 1974–1995, ages ≤12 years at entry into Kaiser Permanente since 1946

Mother’s cancer history recorded in the mother’s medical recordb
Cases (%)Controls (%)
No n = 128Yes n = 56No n = 162Yes n = 33
Mother’s cancer history recorded in the subject’s medical record
No123 (96)24 (43)158 (99)22 (67)
Yes5 (4)32 (57)2 (1)11 (33)
  • a OR, 2.1 (1.46–2.74) using mother’s medical record; OR, 3.5 (2.98–4.01) using subject’s medical record.

  • b Unknowns excluded.