Supporting breast cancer survivors via text messages: reach, acceptability, and utility of EMPOWER-SMS

Purpose This study aims to evaluate the reach, usefulness, acceptability, and factors influencing engagement with a lifestyle-focused text message intervention to support women’s mental and physical health after breast cancer treatment. Methods This study uses a mixed-methods process evaluation nested in the EMPOWER-SMS randomised controlled trial (n = 160; intervention n = 80, wait-list control n = 80). Data sources included screening logs, text message delivery software analytics, intervention feedback survey, and focus groups (n = 16), which were summarised thematically based on the framework approach. Results A total of 387 women met the inclusion criteria (meanage ± SD = 59.3 ± 11.6 years). Participants who declined (n = 227) were significantly older than those who enrolled (n = 160; 62.2 ± 11.1 vs 55.1 ± 11.1 years, respectively, p