Pragmatic Randomized Trial to Evaluate the Impact of Various Interventions to Increase the Uptake of Surveillance Mammography in Eligible Women in Singapore

Breast cancer is the most common cancer among women in Singapore, with more than 70 women out of every 100,000 being diagnosed each year. Early detection through regular mammograms can significantly reduce deaths from breast cancer. Although Singapore has had a national breast cancer screening program (now part of the Screen for Life initiative) for over 20 years, and the government offers substantial subsidies to make screening more affordable, participation remains low at only 30-40%. This low uptake is due to factors like fear, lack of awareness, cultural beliefs, and a perceived low risk of breast cancer. To be effective on a large scale, at least 70% of women need to participate in regular mammography screenings. While researchers in Singapore and Asia have studied the reasons behind low screening rates, there is still a lack of large-scale studies that test different strategies to increase mammography participation in these regions.

This trial will recruit 12,000 women aged 50-69 who have not undergone a mammogram in the past two years. 9000 women will be randomized into five intervention arms. The interventions include: direct mail reminder (Arm 1, control, n=3000), financial incentive (Arm 2, n=1500), lottery incentive (Arm 3, n=1500), health messaging from an influential figure (Arm 4, n=1500), and personal health concierge for appointment scheduling (Arm 5, n=1500). Another 3000 women will be placed in a non-interventional arm (NI arm) for observational analysis, that receives no reminders at all. A post-intervention telephone survey will assess intervention effectiveness.

The primary outcome is mammogram uptake across intervention arms with Arm 1 as a reference. Secondary outcome will be to compare Arm 1 with NI arm. Subgroup analyses will evaluate differences in uptake by sociodemographic factors, such as ethnicity and socioeconomic status. A cost-effectiveness analysis will assess the financial viability of each intervention.

This is the first large-scale study in Singapore and Asia to compare multiple interventions to boost mammography uptake. Findings will provide evidence-based strategies to improve breast cancer screening participation, potentially reducing breast cancer mortality and informing future public health policy.