Table 3

Positive and negative predictive values for single and selecteda two-test strategies for the detection of ≥CIN 3

StrategybPositive predictive valuecNegative predictive valued
Liquid-based (≥ASCUS)8.5%99.8%
HPV (+)8.6%99.8%
Smear (≥ASCUS)11.5%99.5%
Cervigram (≥A)4.9%99.4%
Smear (≥HSIL) or HPV (+)8.8%99.9%
Liquid-based (≥HSIL) or HPV (+)9.0%99.9%
Cervigram (≥P2) or HPV (+)8.8%99.9%
Liquid-based (≥ASCUS) or cervigram (≥P0)7.0%99.9%
Smear (≥HSIL) or liquid-based (≥ASCUS)8.4%99.8%
Smear (≥LSIL) or cervigram (≥P0)9.5%99.6%
  • a For each of the six possible two-technique combinations, the table shows the predictive values for the cut-points with the highest accuracy as measured by Youden’s index.

  • b There were three possible thresholds for conventional and liquid-based cytology (≥ASCUS, ≥LSIL, ≥HSIL), five possible thresholds for cervicography [≥Atypical, ≥Positive(0), ≥Positive(1), ≥Positive(2), ≥Positive(3)], and a single threshold for HPV DNA testing (positive versus negative). Techniques were considered singly and in pairs at all thresholds. Two kinds of combinations were evaluated, either requiring both techniques to be positive or at least one. Overall, there were 112 strategies considered, which were ranked in order of decreasing Youden’s index.

  • c Positive predictive value was calculated as the percentage of women with a positive screening result that had CIN 3 or cancer diagnosed.

  • d Negative predictive value was calculated as the percentage of women with a negative screening result that did not have CIN 3 or cancer diagnosed.