Background Cancer screening programmes have the potential to reduce mortality, but screening programmes can also involve harms such as overdiagnosis and overtreatment. Significant rates of overdiagnosis have been identified as a potential harm of the NHS Breast Screening Programme (BSP) due to the uncertainty around if or how non-invasive cancers will progress into invasive cancers. Importance is therefore placed on encouraging individuals to make an informed choice about whether to participate in screening and any follow-on interventions. Even though it has been explicitly stated that individuals have the freedom to choose, research shows deciding to decline may be met with unsupportive responses and regarded as problematic. Therefore, the aim of this study was to explore the experiences of people who decline screening, treatment and/or other recommended medical interventions after being invited to the NHS BSP.

Methods Qualitative methodology comprising 20 semi-structured interviews conducted via telephone or online (Microsoft Teams) with women who have made the active decision to decline screening, treatment and/or other recommended interventions after being invited to the NHS BSP. Women were recruited through social media, online forums and word of mouth. Interviews were audio-recorded and then transcribed. A thematic analysis of the interview transcripts has been undertaken.

Findings Overall, these women chose to decline at different stages of NHS BSP process and experienced symptoms of breast cancer prior to being invited to programme, during intervals between invitations to programme and after declining participation in the NHS BSP. The women that experienced symptoms outside of the NHS BSP pathway were proactive in seeking medical advice but did not feel as though it influenced their decision to decline participation in the NHS BSP. The majority of women were general practitioners and/or academics and their decision to decline directly or indirectly had implications on their interactions with colleagues and significant others. Since many of the women were medically or scientifically trained, some found themselves sharing their knowledge about the harms of screening with others through activities such as conversations, posting blogs online, or writing published articles. However, some of the women felt that they did not want to share their decision to decline with others due to fear of being misunderstood and/or not wanting to spoil the narratives of those who had chosen to accept screening under the assumption that it can only do good.

Conclusion Due to the women in this study being medically or scientifically trained, they had a better understanding of the information on the benefits and harms of screening compared to the lay population. The decision to decline screening and/or treatment based on this information had an impact on their interactions with others when discussing this topic.