Abstract
This study aimed to assess whether, in the context of communicating risk-based breast cancer screening results, visualizations of risk information consisting of an icon array depicting quantified breast cancer risk and simplified drawings for “qualitative” risk information (e.g. risk factors, screening frequency) offer added value compared to a textual format presenting numerical information. An online experiment was conducted with a 3 (information format: text with numbers – text with risk visualizations – interactive) ×4 (breast cancer risk category: slightly decreased, average, slightly increased, increased) between-subjects design. We recruited n = 1,047 women aged 40–74 years from the general Dutch population, including 413 (39.4%) with lower education and 269 (25.7%) with a family history of breast cancer. Participants viewed hypothetical screening results. Primary outcomes were verbatim and gist comprehension of numerical probability information and verbatim comprehension of qualitative risk information. Secondary outcomes (e.g. affective reactions, perceived likelihood) and health literacy, numeracy, and graph literacy were also assessed. Results showed no significant differences in comprehension between “text with risk visualizations” and “text with numbers” formats. Verbatim comprehension of numerical probability and qualitative risk information was worse in the “interactive” format compared to “text with numbers” format. Those assigned to a non-average risk category exhibited lower verbatim and gist comprehension. Overall, the visualizations tested in this study did not enhance comprehension of riskbased breast cancer screening results compared to a text format with numerical information. Understanding risk-based screening results may be challenging regardless of format, particularly for people assigned to a non-average risk category. potential harms. This has proven difficult, as such information Risk-based breast cancer screening often involves complex screening statistics which can be coun- In the Netherlands, all women between the ages of 50–74 are terintuitive for lay people, such as the risk of overdiagnosis invited biennially for breast cancer screening with mammogra- (Hersch et al., 2018; Petrova et al., 2015; Schwartz et al., 1997). phy. If no breast abnormality is found, a woman receives a letter Although it is not yet clear whether risk-based screening will stating that no abnormality was found and that she will receive be implemented and what it will look like, the results of such a new invitation after two years until she is 75. Although still screening will in any case contain a more multifaceted risk a subject of research, a risk-based approach may be implemented message. For the current study, in consultation with experts, for breast cancer screening in the future (Broeders & Paci, 2015; we assumed a risk-based screening approach in which Fitzgerald et al., 2022; RIVM, 2023). Risk-based screening may a woman is assign