Randomized controlled trial evaluating rapid pre-screen of cervical cytology specimens

A randomized controlled trial of 75,355 cervical cytology specimens was performed comparing rapid pre-screen with no pre-screen. While the percentage of cases receiving a final report of definite high-grade abnormality was higher in the no pre-screen arm (no pre-screen = 0.70%, pre-screen = 0.65%), the percentage of cases receiving a final report of possible or definite high-grade abnormality was essentially identical in the two arms of the trial (no pre-screen = 1.22%, pre-screen = 1.21%). In the randomized trial, one extra cytology report of definite high-grade abnormality was made for every 12,568 slides pre-screened. This level of benefit was reduced by about half when rapid pre-screen was adopted as a routine laboratory practice.