From: Risk factors for breast cancer in postmenopausal Caucasian and Chinese-Canadian women
 | Adjusted Mean (Lower and Upper 95% Confidence Limits) |  |  |  |  | ||
---|---|---|---|---|---|---|---|
 | From | Had lived in both | From | P | |||
 | Mainland | Mainland China | Hong Kong | P b | P c | P d | P e |
 | China | and Hong Kong |  |  |  |  |  |
 | (N = 147) | (N = 141) | (N = 133) |  |  |  |  |
Age at menarche (years)f, g | 14.3 (14.1, 14.6) | 13.7 (13.4, 13.9) | 13.0 (12.7, 13.3) | <0.001 | 0.004 | <0.001 | 0.003 |
Age at first live birth (years)f, h | 24.6 (24.0, 25.2) | 25.7 (25.0, 26.3) | 26.3 (25.6, 27.0) | 0.003 | 0.07 | 0.003 | 0.47 |
Parity (% yes) | 99.0 (95.5, 99.8) | 97.4 (93.1, 99.0) | 94.4 (87.9, 97.5) | 0.06 | 0.86 | 0.12 | 0.53 |
Breastfeeding (% yes) | 95.4 (89.9, 98.0) | 66.7 (56.9, 75.1) | 45.1 (34.1, 56.7) | <0.001 | <0.001 | <0.001 | 0.007 |
Ever used oral contraceptives (% yes) | 29.5 (21.7, 38.8) | 41.4 (32.8, 50.5) | 49.6 (39.9, 59.4) | 0.02 | 0.21 | 0.02 | 0.64 |
Ever used hormone therapy (% yes)i | 12.8 (8.0, 19.7) | 37.8 (30.0, 46.9) | 35.6 (26.8, 45.4) | <0.001 | <0.001 | <0.001 | 0.99 |
Standing height (cm)j | 156.5 (155.4, 157.5) | 156.6 (155.6, 157.5) | 154.5 (153.5, 155.6) | 0.009 | 0.99 | 0.05 | 0.01 |
Weight (kg)j | 55.9 (54.3, 57.6) | 55.5 (54.0, 56.9) | 53.8 (52.3, 55.4) | 0.15 | 0.99 | 0.22 | 0.34 |
BMI (kg/m2)j | 22.9 (22.3, 23.5) | 22.6 (22.1, 23.2) | 22.5 (22.0, 23.1) | 0.77 | 0.99 | 0.99 | 0.99 |
First degree history of breast cancer (% yes)k | 4.4 (1.9, 9.7) | 5.1 (2.3, 10.8) | 14.3 (8.3, 23.4) | 0.02 | 0.99 | 0.06 | 0.07 |
Any benign breast biopsy (% yes) | 2.9 (1.2, 7.0) | 4.4 (1.9, 9.6) | 7.8 (3.9, 14.9) | 0.21 | 0.99 | 0.26 | 0.81 |
Chinese Dietary Acculturation Scorel, m | 0.64 (0.59, 0.68) | 0.58 (0.54, 0.63) | 0.50 (0.46, 0.54) | <0.001 | 0.34 | <0.001 | 0.006 |
Western Dietary Acculturation Scorem, n | 0.62 (0.58, 0.66) | 0.65 (0.61, 0.68) | 0.65 (0.62, 0.68) | 0.50 | 0.99 | 0.78 | 0.99 |