We are researching the potential role of self-sampling in cervical screening. We began planning the research in 2022, and the results will be available this autumn.
Our research advisory group is working with market research company Behaviour and Attitudes on a population survey to understand what people eligible for cervical screening in Ireland think about self-sampling. You can read more about how self-sampling works and how effective it is in our previous blog.
In the survey, we are particularly interested in finding out if self-sampling would appeal to under-screened and never-screened women and people with a cervix in Ireland. We are also asking what kinds of support and information people could need to take a self-sample correctly, such as a talk with their GP or practice nurse, an explanatory video, or a leaflet with pictures; and whether people would be happy to receive their self-sampling kit in the post or if they would rather collect it from their GP or pharmacist.
To increase our knowledge further, we’ve been assessing new international research as it’s published and talking with colleagues in other countries where self-sampling is being offered in cervical screening programmes. In May 2023, we invited Dr Matejka Rebolj, a senior epidemiologist at King’s College London, to present at CervicalCheck’s Annual Colposcopy Conference. With over 20 years’ experience in cervical screening evaluation, Dr Rebolj presented on her recently-published paper advising caution about how countries introduce self-sampling for cervical screening (1). After the conference, we caught up with Dr Rebolj to get some additional advice as we continue our work investigating the potential role of self-sampling in Ireland’s cervical screening programme.
Q&A with Dr Matejka Rebolj
Q. Can you tell us more about your background and how you became interested in the research area of self-sampling for cervical screening?
A. I have worked in cervical cancer screening evaluation and research as an epidemiologist for more than 20 years. I became involved in self-sampling research almost 10 years ago. Since then, self-sampling has progressed from being considered as a secondary screening option for under-screened and never-screened women to a potentially interesting option for sample collection for all women. Many of my colleagues are working on providing evidence on how this could work.
Q. You wrote an article called ‘Widening the offer of human papillomavirus self-sampling to all women eligible for cervical screening: Make haste slowly’ – what are the key messages from that article? Is a cautious approach needed?
A. From various surveys, we know that many women would prefer to collect a sample themselves rather than book an appointment with their screening provider. We also know that this may motivate more women to collect a sample, so that fewer would be affected by this devastating disease.
The usual narrative around self-sampling sounds simple: offer women a choice to collect their own sample or to have one taken by their doctor or nurse, make sure that the laboratories can correctly process both types, and the rest could more or less follow the established processes within a screening programme.
Unsurprisingly, reports from the first countries that have started offering self-sampling to their populations show that it is more complicated than that. For example, it seems that women who have not engaged with cervical screening before need more than just an offer of self-sampling in a standard invitation letter to convince them to take part. Observations like this show that important work still needs to be done to better understand how we could increase the impact of self-sampling in routine screening, and make sure that women are supported in making their decision to use it following the principles of informed consent. This may make the planning for implementation more complex but should not act as a deterrent. In our article, we built a “make haste slowly” case for programmes to reflect on the available scientific evidence and experience shared by those already offering self-sampling in cervical screening; to carefully consider the entire pathway from self-sampling through to laboratory testing, diagnostic process and treatment; to understand how the proposed self-sampling pathway would interact with the existing pathway for women whose samples are collected by a clinician; and to determine whether mitigations might be necessary so that self-sampling could achieve the same success as clinician collection.
Q. As we progress with our work on self-sampling, how do you suggest we approach the possible introduction of self-sampling for cervical screening in Ireland?
A. First, make the most out of the observations reported by those already offering this sampling method. There is plenty there for the rest of us to learn, both in terms of what is working and what is not working. Second, read the literature critically and do not be afraid to accept that none of the screening tests, including those used for self-sampling, is perfect. Imperfection does not equate to uselessness; it just signals that creativity is needed to make the most out of what we have at our disposal. Finally, do not underestimate the importance of collecting local evidence, as the acceptability of self-sampling and informational needs may differ between countries and even population subgroups.
Q. Ireland has a high coverage of close to 80% for cervical screening in our eligible population. Could self-sampling help us to capture those never-screened or under-screened women?
A. An 80% coverage with clinician sampling ranks the Irish screening programme among the more successful ones. Still, studies from settings with similarly successful programmes have suggested that further increases may be possible as some women remain unscreened for practical reasons, and this is what self-sampling addresses directly. One of the things we have learned in 15 years of intensive self-sampling research is that the uptake may vary between countries and may depend on the way self-sampling is offered to women. Therefore, local evidence collected through well-designed studies would clarify how useful self-sampling could be in Ireland overall, and particularly in women who are more likely to die from cervical cancer if they would otherwise remain unscreened.
Q. What are the future research priorities regarding self-sampling for cervical screening?
A. There is still plenty to do both locally and internationally. We need to better understand the local parameters of a successful implementation, such as how to offer self-sampling to women so that they are more likely to accept it; how to keep them engaged to follow through with additional testing if they test positive for HPV; and how to make sure that they also attend for their next screening test when it is due so that this is not a one-off. Though this does not strictly fall under research, we also need to make sure that healthcare providers involved in screening can cope with the changes. The prime example are laboratories, as a different sample type means that sample processing procedures need adjusting. Another example is primary care – if self-sampling turns out to be popular among women, primary care providers may lose some of their expected income. At the same time, while their role in physically taking the sample may change, they will most likely remain the primary point for women seeking information about their screening choices and consequences.
Although the current self-sampling technology is already fairly reliable, there is still scope for improvement to bring its accuracy closer to that of HPV testing on clinician-collected samples, and to develop molecular testing that would remove the need for clinician-collected samples in HPV-positive women. Improvements in technology will likely require a global effort and will require collaboration between scientists with different backgrounds. These studies are expensive, so pooling the funding and access to volunteers willing to donate their samples for research and development would be hugely beneficial.
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As we continue to gather evidence on self-sampling, no changes will be made to the CervicalCheck programme. Changes to population screening programmes in Ireland must first be evaluated by the National Screening Advisory Committee (NSAC). This independent committee makes recommendations to the Minister for Health and the Department of Health. When recommendations are accepted, they are then communicated to the HSE and the National Screening Service begins planning implementation. You can get more information about NSAC and its work programme here.
We would like to thank Dr Rebolj for collaborating with us on this blog.
(1) (Rebolj et al., 2023) - https://onlinelibrary.wiley.com/doi/full/10.1002/ijc.34358