AutoPap system performance in screening for low prevalence and small cell abnormalities.

OBJECTIVE To summarize the design principles of the AutoPap System evaluation score by evaluating slides having a low prevalence of abnormal cells and small cell abnormalities and assessing the evaluation score as a diagnostic tool. STUDY DESIGN Data from two clinical studies conducted using the AutoPap System and data obtained from the evaluation score training slides were analyzed to demonstrate the effectiveness of the evaluation score. The clinical studies included a prospective, intended-use study involving approximately 13,000 slides and a comprehensive sensitivity study using approximately 1,200 slides from five laboratories. The evaluation score training set consisted of 4,174 slides from 10 laboratories. RESULTS The robust design of the AutoPap evaluation score was demonstrated by similar detection capabilities and sensitivities to slides having either a low or high prevalence of abnormal cells. No significant difference in performance was detected between the small cell slides and the comparison groups of carcinoma in situ and invasive squamous carcinoma having normal-sized abnormal cells. In addition, the evaluation scores corresponded well to the diagnostic severity of the slides.