Informing older women about the rationale for cessation of breast cancer screening invitations: A randomised trial of women aged 70-74 years in Australia

Abstract

Women in Australia are no longer invited for mammograms through the breast cancer screening program (BreastScreen) after 74 years due to uncertain benefits and potential harm, but few understand why invitations cease and suspect ageism, cost or lower risk of breast cancer. We tested the impact of providing older women approaching the upper BreastScreen invitation age (70-74 years) with the rationale for breast cancer screening cessation on informed choice.   In a three-arm online randomised controlled trial (n=376), participants read a scenario where they received a letter from BreastScreen indicating their mammogram was clear. They were then randomised to receive 1) no additional information (usual care; control), 2) screening-cessation rationale in text form (e.g., the downsides of screening outweigh the benefits after age 74) or 3) screening-cessation rationale in an animation video. The primary outcome was informed choice defined as adequate knowledge (> within-sample median), and screening attitudes aligned with intention. Data were analysed using chi-square tests.   Intervention arm participants had higher informed choice (animation 40.5%, text 32.0%, controls 17.9%) and knowledge (control: 23.6%; text: 60.2%; animation: 66.1%). Intervention arm participants had lower screening intentions (control: 82.9%; text: 64.9%; animation: 50.4%) and fewer positive screening attitudes for animation arm only (animation: 41.3%, control: 62.6%) (all p<.01).   Informing older women of the rationale for an upper age limit for the national breast screening program increased their informed decision-making. Further research should explore the impact of these interventions in practice and how to support general practitioners to further discuss this with older women.