Page 47 - Screening for Cervical Cancer: Systematic Evidence Review
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Chapter III. Results
Evidence Report/Technology Assessment, Number 5: Evaluation of Cervical Cytology; two were
new articles on screening tools not covered by either systematic review (e.g., unaided visual
inspection of the cervix, and cervicography); and one article was a final publication of a study
that had been reviewed in draft form for Cervical Cytology report and had minor changes in the
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final published results.
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The Cervical Cytology report was published in February 1999 and updated in January
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2000 for peer-reviewed publication. The report includes studies with and without validation of
screening tests by clinical evaluation. For convenience, the portions of the evidence tables from
that report that are related to new technologies are reproduced and updated in this report
(Evidence Table 2). In collaboration with the authors of the cervical cytology report, the RTI-
UNC EPC team abstracted new articles in a comparable fashion.
As described in the methods section, we had planned to focus on studies that used
colposcopy or histology as a gold standard for evaluation of performance of the screening
system. However, such publications remain rare. At completion, we extended the prior Cervical
Cytology review by updating final data from one article, adding three new articles based on a
cytological reference standard with or without a subset of histologic verification, and adding one
with an adequate colposcopic and histologic reference standard. This study applied a definitive
clinical reference standard to a random sample of women with normal screening test results and
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permitted calculation of all test characteristics including estimation of specificity.
Evidence Table 2 (Appendix C) summarizes 29 studies that evaluate the performance of
new technologies for preparing or interpreting cervical cytology specimens: 9 evaluating liquid-
based cytology collection systems (ThinPrep ); 13, neural-net rescreening or prescreening
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