Assessing slide coverage by cytoscreeners during the primary screening of cervical smears, using the AxioHOME Microscope system.

We have used the HOME Microscope system to examine the screening patterns of cytotechnologists who undertake the primary screening of cervical smears, in order to measure accuracy of screening against screening time, slide coverage, and mean screening rate. Twelve cytotechnologists engaged routinely on cervical screening volunteered for this study. They were asked to perform primary screening of 10 test slides under normal laboratory conditions in the normal way. Slide coverage and screening time were recorded on the HOME system. Slide maps were prepared and the results analysed. The exercise demonstrated that all primary screeners fail at some point to scan the whole of the slide during primary screening. The maps produced by the HOME system clearly demonstrated that 5 different types of error can occur that lead to incomplete coverage of the slide. Mean slide coverage was 84%, and some individuals averaged only 66% coverage. The results show that there is a major problem in the education of some individual cytotechnologists in slide coverage. This could be rectified by the incorporation of a HOME system into every training centre, and the establishment of a protocol for assessment of slide coverage in competence examinations. Furthermore, the exercise has shown that even those individuals who normally attain a good standard of slide coverage would be able to improve slide coverage given access to the daily use of a HOME Microscope, or a system with equivalent screening/reviewing functionality.