High coverage is essential for an effective screening programme but not all women will ever be screened. It is important to distinguish between women who have made a permanent commitment not to get screened, from those who hold positive attitudes to screening but for some reason fail to participate. Studies on factors related to non-participation may help to identify barriers in screening, and knowledge together with new technologies may help to overcome these barriers.
Our experience is based on 1.3 million women aged 26 ΜΆ 69 years living in Norway as of December 31, 2012. We used several national registers to obtain individual sociodemographic and health related data. We defined non-participants as no Pap smear registered within the last screening interval. Non-participants were randomized to receive a self-sampling device (n=729) or a second reminder letter (n=2539).
34% of women were non-participants. Known risk factors for HPV infection such as unemployment, low education, low income and being an immigrant were barriers to screening in a country where organized programme and equal access to health care exist. Self-sampling increased screening attendance from 22%, in the control group, to 33% in the self-sampling group.
In general, socioeconomic inequalities with regard to screening participation exist only in countries with opportunistic screening. Thus, an organized nationwide screening, when offered free of charge, seems to reach women at a higher risk of cancer who are less likely to participate spontaneously.
Postal or telephone reminders and pre-assigned appointment times and locations in the invitation letter are means to reach more woman in a screening practice. Furthermore, invitation sent by the general practitioner (GP) increases screening uptake compared to an invitation letter from a screening organization.
Self-sampling increases screening participation and might be even more effective than a reminder in attracting underserved women. One plausible explanation is that immigrants are overrepresented among non-participants and they face special barriers to screening some of which are religious, cultural and language related.
More than half of screening non-participants visit their GP regularly. This represents a good opportunity for improving screening coverage. It requires, however, that GPs actively encourage woman to screening uptake and offer self-sampling devices to those who don`t comply with a pelvic examination.
Women who don`t regularly attend screening are characterized by diversity. To reach the maximal screening coverage requires various approaches fitting to the characteristics of both the programme and the target population.