Table 1.

Comparison of cases and controls on demographics and selected endometrial cancer risk factors

Cases (n = 1,204)Controls (n = 1,212)P
Age (mean ± SD)54.9 ± 8.555.1 ± 8.50.75*
Education (%)
    No formal education7.911.0
    Elementary education14.112.9
    Middle and high school62.963.3
    Professional, college and above15.112.80.03
Marital status (%)
    Unmarried1.51.1
    Married or cohabiting87.687.6
    Separated/divorced/widowed10.911.30.63
Family income in previous year, yuan (%)
    <10,00011.611.2
    10,000-14,99921.721.3
    15,000-19,99919.918.5
    20,000-29,99921.925.6
    ≥30,00024.923.40.33
No. pregnancies (%)
    Never7.43.6
    116.913.8
    225.226.0
    322.324.9
    416.917.6
    ≥511.314.1<0.01
Cancer among first-degree relatives (%)8.54.4<0.01
Natural menopause (%)97.099.1<0.01
Oral conceptive use (%)18.524.9<0.01
Hormone replacement therapy (%)4.44.00.66
Regular exercise (%)28.733.50.01
Age at menarche§14.0 (13.0, 16.0)15.0 (13.0, 16.0)<0.01*
Age at menopause (among postmenopausal women)§50.3 (48.6, 52.5)49.6 (47.3, 51.1)<0.01*
Years of menstruation§33.3 (30.1, 36.1)31.5 (28.2, 34.4)<0.01*
BMI§25.2 (22.9, 28.1)23.5 (21.4, 26.0)<0.01*
Waist-to-hip circumference ratio§0.84 (0.81, 0.87)0.81 (0.78, 0.85)<0.01*
  • NOTE: Subjects with missing values were excluded from the analysis.

  • * Nonvariable test on continuous variables.

  • χ2 test was used to compare the distribution of categorical variables.

  • Family history of colorectal, endometrial, or breast cancer among first-degree relatives.

  • § Median (25th, 75th percentile) is presented.