Table 1. Comparison of endometrial cancer cases and controls on demographic characteristics and selected risk factors, Shanghai Endometrial Cancer Study, 1997–2003.
| Factor | Cases (n = 1204) | Controls (n = 1212) | P |
| Median age (25th, 75th percentile) | 54.3(48.5, 62.1) | 54.5(48.5, 62.6) | 0.77 |
| Education level (%) | |||
| No formal education | 7.9 | 11.0 | |
| Elementary | 14.1 | 13.0 | |
| Junior high school | 37.0 | 36.4 | |
| High school | 25.8 | 26.9 | |
| Post-high school/College | 15.1 | 12.8 | 0.05 |
| Physical activity in METs (mean ± SD) | 10.5±7.3 | 11.0±4.6 | 0.05 |
| Oral contraceptive use (%) | 18.5 | 24.9 | <0.01 |
| Cancer history among first-degree relatives (%) | 35.2 | 27.9 | <0.01 |
| Nulliparous (%) | 7.4 | 3.6 | <0.01 |
| No. of pregnancies (mean ± SD) | 2.6±1.5 | 2.9±1.5 | <0.01 |
| BMI (kg/m2) (mean ± SD) | 25.7±4.2 | 23.8±3.5 | <0.01 |
| Alcohol consumption (%) | 2.8 | 5.4 | <0.01 |
| History of diabetes (%) | 15.3 | 6.9 | <0.01 |
| Time of menstruation (years, mean ± SD) | 32.8±4.9 | 30.6±5.4 | <0.01 |
| Menopause (%) | 58.3 | 63.1 | 0.01 |
| Use of HRT (%) | 4.4 | 4.0 | 0.66 |
MET, metabolic equivalent; SD, standard deviation; BMI, body mass index; HRT, hormone replacement therapy. Missing values have been excluded. P value for t test (continuous variables) or χ2 test (categorical variables).