Table 1.

Characteristics of cases and controls

Cases (n = 1,600)Controls (n = 1,949)
Age (y)*64.9 ± 9.865.0 ± 10.1
Sex
    Male895 (55.9)1,036 (53.2)
    Female705 (44.1)913 (46.8)
Race
    White, not Hispanic1,461 (91.4)1,814 (93.1)
    Hispanic62 (3.9)78 (4.0)
    African American72 (4.5)53 (2.7)
    Other4 (0.2)3 (0.2)
Study center
    Kaiser769 (48.1)804 (41.3)
    Utah578 (36.1)796 (40.8)
    Minnesota253 (15.8)349 (17.9)
Education
    <12 y262 (16.4)249 (12.8)
    High school graduate451 (28.2)545 (28.0)
    Some college or post-high school530 (33.1)634 (32.6)
    College graduate or higher357 (22.3)520 (26.7)
Income
    <$20,000401 (27.0)455 (24.8)
    $20,000-$40,000533 (35.9)627 (34.2)
    $40,000-$60,000348 (23.4)438 (23.9)
    >$60,000203 (13.7)313 (17.1)
Mean UV-weighted hours of sun exposure (UV index h/wk)85.8 ± 70.987.4 ± 68.7
Mean total vitamin D (μg/d)10.6 ± 6.011.1 ± 6.2
Multivitamin supplement use520 (32.5)654 (33.6)
Vitamin D supplement use25 (1.6)53 (2.7)
Tumor site
    Distal790 (49.4)-
    Proximal771 (48.2)-
    Unknown39 (2.4)-

NOTE: Continuous variables are displayed as mean values ± SD, and frequencies are displayed as counts (percentage).

  • *Defined as age at diagnosis for cases and age at recruitment for controls.

  • Energy adjusted (residual method) dietary intake.

  • Supplement use defined as regular use (at least three times a week for at least one month) over the referent period.