Figure 1

NOTE: Data are shown on cumulative incidence of CIN3+ by enrollment HPV test versus Pap smear. “Pap−“ means Pap-negative (NILM). “Pap+” means any abnormality (non-NILM). In Panel A, HPV test results are in blue, Pap smear test results are in black, positive test results are solid lines, and negative test results are dashed lines. Prevalent CIN3+ is plotted at time 0 (enrollment) and incident CIN3+ is plotted from that point. The HPV test more clearly separated high-risk women from low-risk women than the Pap smear because both (1) HPV+ women at enrollment had higher CIN3+ risk than the Pap+ women after 3 years (5.0% vs. 3.8%, p=0.046) and 5-years (7.6% vs. 4.7%, p=0.001), and (2) HPV− women at enrollment had lower CIN3+ risk than Pap− women at enrollment after 3-years (0.063% vs. 0.17%, p=0.001) and after 5-years (0.17% vs. 0.36%, p=0.02). In Panel B, HPV+ is in blue, HPV− is in black, Pap+ is solid and Pap− is dashed. Pap+ strongly modified risks for the HPV+ at three-years (10.0% vs. 3.1%, p<0.001) and five-years (12.1% vs. 5.9%, p<0.001), but not for the HPV− either at three-years (0.52% vs. 0.047%, p<0.001) or five-years (0.86% vs. 0.16%, p<0.001), although risks are statistically distinguishable. Comparing to Panel A, also being Pap-did not reduce CIN3+ risk from just being HPV− either at three-years (0.047% vs. 0.063%, p=0.6) or five-years (0.16% vs. 0.17%, p=0.8). See supplemental table 1 for 95% confidence intervals for all risk estimates. The number of women in each group are: HPV-positive: 16,757; HPV-negative: 315,061; Pap-positive: 12,641; Pap-negative: 319,177; HPV-positive/Pap-positive: 4,549; HPV-positive/Pap-negative: 12,208; HPV-negative/Pap-positive: 8,092; HPV-negative/Pap-negative: 306,969.