Table 1.

Characteristics by level of education, the NOWAC study, 1991-2001

nEducation (y)
7-9 (%)10-12 (%)13-16 (%)≥17 (%)
Total96,48528.834.725.311.2
Age at entry into the cohort (y)
    30-3926,01714.828.535.135.2
    40-4945,05642.348.848.048.6
    50-5915,26521.714.811.912.8
    60-6910,14721.27.95.03.4
Mean (SD) age at cohort enrollment (y)50.0 (9.7)45.1 (8.3)43.5 (7.7)43.3 (7.2)
Smoking status
    Current38,35046.044.534.226.2
    Former23,19124.023.824.626.4
    Never33,68130.031.741.247.5
Age at start smoking (y)
    <2036,41261.863.656.650.0
    ≥2024,08438.236.443.450.0
No. pack-years smoked
    1-1987,20089.592.095.195.8
    ≥207,07410.57.84.94.2
Perceived health
    Poor or very poor7,38114.17.65.14.8
    Good or very good78,08385.992.494.995.2
Total intake of fat (g/d)
    <5060,40469.177.779.678.0
    ≥5019,50630.922.320.422.0
Age at first birth (y)
    <2011,87123.314.55.22.9
    20-2442,33154.854.042.126.7
    25-2924,20216.823.939.344.7
    ≥308,8255.17.613.425.7
Mean (SD) age at first birth22.3 (3.8)23.3 (4.0)25.2 (4.1)26.9 (4.4)
Parity at entry
    Nulliparous9,2227.18.011.017.5
    1 child11,5409.712.212.715.3
    2 children39,41434.344.344.039.8
    ≥3 children36,30749.035.432.327.4
Mean (SD) no. children2.6 (1.4)2.2 (1.1)2.1 (1.1)1.8 (1.2)
BMI (kg/m2)
    <18.52,5712.42.73.03.1
    18.5-24.564,62059.269.574.577.5
    25-29.521,10629.222.118.315.7
    ≥305,7639.25.84.23.6
Mean (SD) BMI24.6 (4.1)23.6 (3.6)23.1 (3.4)22.8 (3.3)
Change in BMI since age 18 y (units)
    <017,30218.518.321.122.6
    0-444,71443.051.255.056.8
    >426,38438.530.623.920.6
Mean (SD) height (cm)165.1 (5.6)166.2 (5.5)166.9 (5.6)167.5 (5.6)
Use of oral contraceptives
    Ever used52,31641.257.764.067.0
    Never used41,54958.842.336.033.0
Ever use of HRT among women ages ≥50 y at entry
    Yes9,39030.640.743.648.0
    No16,02269.459.356.452.0
Menopausal status at entry
    Premenopausal72,67059.078.284.887.1
    Postmenopausal23,81541.021.815.212.9
Daily consumption of alcohol (g)
    Teetotaller26,13338.427.324.320.7
    0.1-3.943,60948.450.647.443.2
    4.0-9.915,73210.317.121.926.0
    ≥104,8142.95.06.410.1
Mean (SD) alcohol consumption1.9 (5.0)2.8 (5.5)3.2 (4.9)4.0 (5.7)
Frequency of cytologic screening
    Never3,0585.43.22.93.5
    Less often than every third year21,83431.124.925.128.1
    Every third year or more often55,52163.471.972.068.4
Participation in mammography screening before entry among women ages ≥50 y
    Yes9,67631.943.045.042.5
    No15,73668.157.055.057.5
No. sunburns yearly
    010,14521.212.39.16.8
    155,03667.773.072.872.3
    ≥211,80411.014.618.120.9
Region of living
    South or middle of Norway75,16465.781.285.083.0
    Northern Norway21,32134.318.815.017.0