Table 1

Comparison of cases and controls by selected demographics and breast cancer risk factors, Shanghai Breast Cancer Study, 1996–1998

Cases (n = 186)aControls (n = 200)aOR (95% CI)
Demographic factors
Age (yr)47 (42, 53)b46 (41, 55)b
Education ≥ high school40.343.00.9 (0.6–1.3)
Major risk factors
First-degree relative with breast cancer1.62.00.8 (0.2–3.6)
Ever diagnosed with breast fibroadenoma9.74.02.6 (1.1–6.1)
No regular leisure physical activity80.169.01.8 (1.1–2.9)
Waist:hip ratio ≥0.8521.618.51.2 (0.7–2.0)
Body mass index ≥2527.022.51.3 (0.8–2.0)
Age at menarche ≤12 yr9.27.51.2 (0.6–2.6)
Age at menopause ≥50 yrc50.038.01.6 (0.8–3.2)
Age at first live birth ≥30 yrd25.616.01.8 (1.1–3.0)
  • a Unless otherwise specified, percentages are presented.

  • b Median (25th, 75th percentile) are presented.

  • c Among postmenopausal women.

  • d Among parous women.