Table 1.

Distribution of baseline characteristics by outcome status

Variable*Cases (n = 329)
Controls (n = 621)
n (%)
Age, y
    <2575 (22.8)160 (25.8)
    25-2970 (21.3)126 (20.3)
    30-3460 (18.2)114 (18.4)
    35-3963 (19.2)84 (13.5)
    40-4424 (7.3)48 (7.7)
    45-4921 (6.4)44 (7.1)
    ≥5016 (4.9)44 (7.1)
Ethnicity
    French Canadian209 (63.5)380 (61.2)
    English Canadian41 (12.5)44 (7.1)
    Other79 (24.0)197 (31.7)
Highest level of schooling
    Elementary5 (1.5)9 (1.5)
    Secondary86 (26.1)134 (21.6)
    College/undergraduate university204 (62.0)402 (64.7)
    Graduate31 (9.4)75 (12.1)
Cigarette smoking
    Never126 (38.3)331 (53.3)
    Former72 (21.9)121 (19.5)
    Current128 (38.9)167 (26.9)
No. pregnancies
    0123 (37.4)282 (45.4)
    171 (21.6)111 (17.9)
    255 (16.7)103 (16.6)
    ≥377 (23.4)122 (19.7)
Oral contraceptive use
    Never31 (9.4)63 (10.1)
    Former159 (48.3)301 (48.5)
    Current135 (41.0)246 (39.6)
Age at menarche, y
    8-1163 (19.2)117 (18.8)
    1298 (29.8)184 (29.6)
    1380 (24.3)155 (25.0)
    ≥1485 (25.8)159 (25.6)
Use of hormones to treat menopause/infertility
    Never298 (90.6)538 (86.6)
    Ever25 (7.6)69 (11.1)
Age at first vaginal intercourse, y
    <16105 (31.9)137 (22.1)
    16-1793 (28.3)187 (30.1)
    1848 (14.6)102 (16.4)
    ≥1969 (21.0)171 (27.5)
Lifetime no. male vaginal sexual partners
    ≤124 (7.3)105 (16.9)
    2-476 (23.1)190 (30.6)
    5-894 (28.6)155 (25.0)
    >8129 (39.2)163 (26.3)
HPV status
    HPV negative12 (3.7)437 (70.4)
    Positive for any HPV type312 (95.4)184 (29.6)
        Positive for only a low-risk HPV type12 (3.7)72 (11.6)
        Positive for at least one high-risk HPV type300 (91.7)112 (18.0)
            Positive for any high-risk HPV type except HPV-16/HPV-18109 (33.3)80 (12.9)
  • * Missing data are not listed. Total frequencies may slightly differ from the total number of cases and controls because of missing data for some variables.