Comparison of cases and controls by selected descriptive characteristics, Shanghai Breast Cancer Study, 1996-1998
| Subject characteristic . | Cases (n = 1,132) . | Controls (n = 1,222) . | P* . | |||
|---|---|---|---|---|---|---|
| Age (y), mean ± SD | 47.6 ± 8.0 | 47.2 ± 8.7 | 0.20 | |||
| Education (%) | ||||||
| Elementary school or below | 12.3 | 14.6 | ||||
| Middle or high school | 75.7 | 75.4 | ||||
| College or above | 12.0 | 10.1 | 0.11 | |||
| Breast cancer in first-degree relative (%) | 3.4 | 2.4 | 0.12 | |||
| Ever had breast fibroadenoma (%) | 9.7 | 5.2 | <0.01 | |||
| Age at menarche (y) | 14.5 ± 1.6 | 14.7 ± 1.7 | <0.01 | |||
| Age at first live birth (y), mean ± SD | 26.8 ± 4.1 | 26.2 ± 3.8 | <0.01 | |||
| Postmenopausal (%) | 33.2 | 36.2 | 0.13 | |||
| Age at menopause (y), mean ± SD | 48.2 ± 4.6 | 47.5 ± 5.0 | 0.04 | |||
| Physically active past 10 y (%) | 19.2 | 25.7 | <0.01 | |||
| BMI (kg/m2), mean ± SD | 23.5 ± 3.4 | 23.2 ± 3.4 | 0.03 | |||
| WHR, mean ± SD | 0.81 ± 0.06 | 0.80 ± 0.06 | <0.01 | |||
| Subject characteristic . | Cases (n = 1,132) . | Controls (n = 1,222) . | P* . | |||
|---|---|---|---|---|---|---|
| Age (y), mean ± SD | 47.6 ± 8.0 | 47.2 ± 8.7 | 0.20 | |||
| Education (%) | ||||||
| Elementary school or below | 12.3 | 14.6 | ||||
| Middle or high school | 75.7 | 75.4 | ||||
| College or above | 12.0 | 10.1 | 0.11 | |||
| Breast cancer in first-degree relative (%) | 3.4 | 2.4 | 0.12 | |||
| Ever had breast fibroadenoma (%) | 9.7 | 5.2 | <0.01 | |||
| Age at menarche (y) | 14.5 ± 1.6 | 14.7 ± 1.7 | <0.01 | |||
| Age at first live birth (y), mean ± SD | 26.8 ± 4.1 | 26.2 ± 3.8 | <0.01 | |||
| Postmenopausal (%) | 33.2 | 36.2 | 0.13 | |||
| Age at menopause (y), mean ± SD | 48.2 ± 4.6 | 47.5 ± 5.0 | 0.04 | |||
| Physically active past 10 y (%) | 19.2 | 25.7 | <0.01 | |||
| BMI (kg/m2), mean ± SD | 23.5 ± 3.4 | 23.2 ± 3.4 | 0.03 | |||
| WHR, mean ± SD | 0.81 ± 0.06 | 0.80 ± 0.06 | <0.01 | |||
For χ2 test (categorical variables) or t test (continuous variables).