Hologic ThinPrep 5000 - Page 18

ThinPrep™ 5000 System Instructions for Use English AW-22289-001 Rev. 003 11-2021 12/36
One pathologist served as an independent reviewer for the six clinical sites, receiving both slides
from cases where the two methods were either abnormal or discrepant. Since a true reference
cannot be determined in such studies and therefore true sensitivity cannot be calculated, the use
of an expert cytologic review provides an alternative to histologic confirmation by biopsy or
human papillomavirus (HPV) testing as a means for determining the reference diagnosis.
The reference diagnosis was the more severe diagnosis from either of the ThinPrep or
conventional Pap slides as determined by the independent pathologist. The number of slides
diagnosed as abnormal at each site, compared to the reference diagnosis of the independent
pathologist, provides the proportion of LSIL or more severe lesions (Table 8) and the proportion
of ASCUS/AGUS or more severe lesions (Table 9). The statistical analysis allows a comparison of
the two methods and a determination of which method is favored when using the independent
pathologist for expert cytologic review as the adjudicator of the final diagnosis.
Table 8: Independent Pathologist Results by Site, LSIL and More Severe Lesions
Site Cases Positive
by
Independent
Pathologist
ThinPrep
Positive
Conventional
Positive
p-Value Method Favored
S1
50 33 25 0.170 Neither
S2
65 48 33 0.042 ThinPrep
S3
77 54 33 <0.001 ThinPrep
H1
116 102 81 <0.001 ThinPrep
H2
115 86 90 0.876 Neither
H3
126 120 112 0.170 Neither
For LSIL and more severe lesions, the diagnostic comparison statistically favored the ThinPrep method at
three sites and was statistically equivalent at three sites.