Table 1

Number of subjects in initial subcohort, HPV positivity, and distribution of case-control groups according to selected variables stratified by oncogenic risk

VariableSubcohortHPV positivity (%) in initial subcohorta (N = 1425)No. subjects in case-control samples
NononcogenicOncogenicHPV 16Controlb (N = 512)Exclusive nononcogenicc (N = 123)Exclusive oncogenicd (N = 94)HPV 16e (N = 60)
Age (yr)
18–2426318.624.34.990223413
25–3455915.615.75.0214503728
35–4443112.510.02.8154331712
45–6017214.08.74.1541867
Race
White93613.514.03.8351706336
Non-White48718.116.24.9161533124
Education
Elementary117813.814.64.4424917552
High school24621.115.43.38732198
Income (US $/mo)
<33467915.216.65.6237634538
≥33471814.513.03.1265574722
Age at first intercourse (yr)
≤1539915.018.55.8128314123
16–1735817.018.76.1133292122
18–1928914.514.52.810925198
20–5037913.57.11.814238137
Lifetime sexual partners
162511.710.62.7249513517
2–349614.316.94.8172394124
≥430423.019.76.391331819
Sexual partners past 5 yr
0–1111011.910.93.1437886934
2+31326.228.48.375352526
Sexual partners past yr
0–1133713.813.24.04991138253
2+6740.346.39.0118106
Anal intercourse
Never88815.513.73.7311835333
Ever53714.216.45.0201404127
Yr of OC use
Never used19118.816.82.1641674
<6 years71015.414.93.9261665628
≥6 years42312.114.45.7149342924
Pregnancies
0–121718.420.34.679191810
2–361914.413.23.1232584119
4–533113.314.84.8115231916
6+24214.913.66.282211515
Previous Pap tests
0–575715.517.05.0257666038
≥665314.211.83.2252553321
Vaginal douching
Never/rarely128715.314.54.04621188352
Frequently13812.316.75.8505118
Hygienic tampons
Never126014.814.03.74521117647
Ever16516.420.67.960121813
Smoking
Never70113.413.64.3280484230
Former24516.311.05.376261313
Present47916.718.43.5156493917
  • a Percent positive by HPV infection group in initial subcohort, including women with multiple infections.

  • b Subjects who tested consistently negative in first four visits.

  • c Subjects who harbored exclusively nononcogenic HPV types in first four visits.

  • d Subjects who harbored exclusively oncogenic HPV types in first four visits.

  • e Subjects who harbored HPV 16 in any of first four visits with or without other HPV types.