BACKGROUND: We compared the sensitivity and specificity of liquid-based cytology (LBC) and computer-assisted reading for SurePath/FocalPoint and ThinPrep with those of manually read conventional cytology in routine cervical screening in four Danish laboratories.

METHODS: Using data from five nationwide registers, technological phases were identified by slide preparation, reading technique, and triage of borderline cytology. Trends in the detection of cervical intraepithelial neoplasia (CIN) were an indicator of the technology's relative sensitivity, and trends in false-positive tests an indicator of relative specificity.

RESULTS: At 23-29 years, SurePath/FocalPoint statistically significantly increased the detection of ⩾CIN3 by 85% compared with manually read conventional cytology. The 11% increase with ThinPrep was not significant. At 30-44 years, the increase with SurePath/FocalPoint was 58%; the 16% increase with ThinPrep was not significant. At 45-59 years, both technologies led to nonsignificant decreases in the detection. SurePath/FocalPoint doubled the frequency of false-positive tests at any age. With ThinPrep, these proportions remained the same at 23-29 years, but decreased by two-thirds at 45-59 years. In a fourth laboratory with continuous use of manually read conventional cytology, no such trends were seen.

CONCLUSIONS: The sensitivity and specificity of modern LBC and computer-assisted reading technologies may be brand- and age-dependent.