Trend analysis of process quality indicators for the Korean National Cervical Cancer Screening Program from 2005 to 2013

Objective: This study sought to examine changes in trends for quality indicators of the population-based Korean National Cancer Screening Program (KNCSP) for cervical cancer from years 2005 to 2013. Methods: Our study data were derived from the KNCSP database. Cervical cancer diagnosis information was ascertained through linkage with the Korean National Cancer Registry and the KNCSP database. Performance measures for cervical cancer screening were estimated, including participation rate, positive rate, crude detection rate (CDR), interval cancer rate (ICR), positive predictive value (PPV), sensitivity, and specificity. Joinpoint analysis was applied to calculate annual percentage changes (APCs) in all indicators according to socio-demographic factors. Results: A significant increasing trend was noted in participation rates (APC=13.4%; 95% confidence interval [CI]=10.5, 16.4). PPV and specificity increased from years 2005 to 2009 and remained stable till 2013. An increasing trend was discovered in CDRs for cervical cancer in situ (APC=3.9%; 95% CI=1.0, 6.9), whereas a decreasing trend was observed in ICRs for invasive cervical cancer (APC=-2.5%; 95% CI=-4.5, -0.5). Medical Aid recipients and women older than 70 years showed the lowest participation rates, but higher CDRs and ICRs, compared to other groups. In general, most of the quality indicators for cervical cancer screening improved from 2005 to 2009 and remained stable to 2013. Conclusion: The KNCSP for cervical cancer in Korea has improved in terms of participation rate and accuracy of the screening test. These results may be attributed to the National Quality Improvement Program for KNCSP.