Nordic cervical screening on common ground

Nordscreen is a much welcomed initiative to collect and present data on cervical screening activities in the Nordic countries. The database and the interactive webpage are described in this issue of Acta Oncologica [1]. The Nordic countries have much in common in these areas: Tax-funded health-care systems; organized cervical screening since at least two decades; a common commitment to public health with governments’ responsibility for the prevention of disease, equally for the entire population; and the personal number system, decisive for effective population-based screening and for monitoring and improving quality by linkage of data. These features allow comparison of data between the countries.

The outcome of cervical cancer screening in the Nordic countries has been described in a multitude of publications that not only document efficacy but also demonstrate challenges and differences between the countries [2–10]. Lack of standardization, however, may render comparisons misleading. Participation in screening is fundamental for effectiveness. Sophisticated tests and high quality investigations can be implemented in vain if the target population do not choose to  participate. Population-based screening provides a means to increase participation, particularly in less resourceful groups. It is therefore sensible that Nordscreen focuses on screening coverage. At the same time, comparison between common standards clarifies particularities. Finland collects the majority of the samples outside of the screening program and since these data are not accessible, Finnish data on coverage are less relevant. Denmark that has the highest mortality from cervical cancer in Western Europe shows no data. Iceland shows coverage that exceeds 100% in some age groups based on the method for calculation of coverage.

The Nordscreen webpage is an achievement and an important step toward harmonization. It provides a user-friendly tool to tailor statistics in real time and make it possible to compare relevant age groups and account for differences in the age groups invited. Data might not always give answers but certainly will pose questions and trigger investigations to improve quality of cervical cancer screening. Some of the patterns raise questions. Why is coverage slowly declining over the years in Iceland, and perhaps also in Norway? Why are there substantial differences across age groups in Norway? The authors rightfully point to the need to expand data for future comparisons and analyses. It would be useful to present results based on HPV tests and cytology separately, and to provide basic test results and data on low-grade and high-grade squamous intraepithelial lesions in cytology specimens. Direct comparison of such parameters could give an indication of the resources needed in the transition to primary HPV-screening and the burden of positive results on the screened women. Additional highly relevant quality parameters could be colposcopy data, histopathology data and treatments of precancerous lesions. The Nordic network could have an important role in stimulating and encouraging regional and national reporting of such data. As with all web resources, keeping data up-to-date will be a challenge also for the Nordscreen to remain a trustworthy source of information in the rapidly changing area of cervical cancer screening.

The mere establishment and existence of the Nordscreen platform will challenge the country that has not delivered data to do so, stimulate the country with incomplete data to retrieve these from all laboratories and encourage all countries to look their data with relevant and corresponding references. The Nordic countries can also stand as a model for the Baltic countries and indeed Estonia has already been invited and provides data from its newly established screening program. This project is also a road model for other cancer screening programs in the Nordic countries, who should consider joining the initiative.

Disclosure statement

No potential conflict of interest was reported by the author.