Effectiveness of an mHealth Intervention to Increase Participation in Breast Cancer Screening (Breast Cancer ATICA Study): A Pragmatic Randomized Controlled Trial

Abstract Implementation of invitation systems has been shown to increase breast cancer screening rates. However, implementation of active outreach strategies in Latin American programs is limited. We conducted a pragmatic randomized controlled trial—the breast cancer ATICA study—to evaluate the effectiveness and implementation of a digital messaging–based intervention to increase breast cancer screening. A total of 248 Argentinian women ages 50+ years were recruited from 10 health care centers in Santa Fe, Argentina, and randomly assigned (1:1) to the intervention (n = 123) or control group (n = 125). The intervention included up to four Short Message Service (SMS) messages inviting participants to schedule an appointment for mammography through WhatsApp or the usual care control group (n = 125). Effectiveness outcomes were the proportion of women who underwent mammography within 105 or 45 days of enrollment. The reach, effectiveness, adoption, implementation, and maintenance framework was used to evaluate the implementation of the intervention. Our results showed that women in the intervention group (n = 123) were significantly more likely than women in the control group (n = 125) to undergo a mammography within 105 days (23.6% vs. 6.4%, difference 17%, 95% confidence interval, 7.7%–27.0%) and within 45 days (15.4% vs. 3.2%; difference 12%, 95% confidence interval, 4.3%–20.0%; P = 0.02). Our results also showed high acceptability and appropriateness of the intervention. Our study demonstrates that sending consecutive SMS messages, including a WhatsApp number to ask for an appointment, effectively increased breast cancer screening. This mobile health intervention could be an excellent option to improve access to breast cancer screening in low- and middle-resource settings in which active invitation systems are challenging to implement. Prevention Relevance: Breast cancer remains a significant public health concern, and strategies to improve access to screening are urgently needed. This study is one of the first pragmatic randomized controlled trials in Latin America that demonstrate the effectiveness and real-world implementation of an SMS-based intervention to increase participation in breast cancer screening.