1. Finnish Cancer Registry, Helsinki, Finland;
2. Karolinska Institutet, Stockholm, Sweden;
3. Regional Cancer Center Stockholm-Gotland, Stockholm, Sweden;
4. Department of Cervical Cancer Screening, Cancer Registry of Norway, Oslo, Norway;
5. Cancer Detection Clinic, The Icelandic Cancer Society, Reykjavik, Iceland;
6. National Institute for Health Development, Tallinn, Estonia