Rapid screening of cervical smears as a method of internal quality assurance

摘要

INTRODUCTION: One of the most frequently cited disadvantages of cervical cancer screening is its high false negative rate. The most widely used quality assurance method is 10% random re-screening. Recent studies have shown that 100% rapid re-screening is an efficient method for reduction of the false negative rate. OBJECTIVE: The aim of this study was to compare the performance of 100% rapid re-screening with that of 10% random re-screening as an internal quality assurance method. METHODS: 2,750 first screening negative smears were submitted to 100% rapid re-screening by a senior cytotechnologist followed by 10% random re-screening by another senior cytotechnologist. After re-screening, all smears were analyzed by two independent cytopathologists. Whenever results were divergent the smears were analyzed by a third cytopathologist and the panel established a consensus gold standard diagnosis. RESULTS: 98 suspect smears were selected by rapid re-screening, 62 of which were confirmed as abnormal by the gold standard: 45 Ascus, 11 LSIL and six HSIL (sensitivity 73.8%). Of the nine abnormal smears detected by the 10% random re-screening, six were confirmed by the gold standard, three Ascus, two LSIL and one HSIL (sensitivity 50%). The gold standard detected 57 Ascus, ten LSIL and five HSIL cases among the 2,489 smears that were not submitted to 10% re-screening. CONCLUSIONS: 100% rapid re-screening is an efficient alternative for reduction of cervical screening false negative rates. It also allowed to monitor the individual performance of members of the team.