Supporting health literacy using an interactive app for symptom management during radiotherapy for prostate cancer

•Patient-reported outcomes were collected through an app during cancer treatment.•Health literacy and self-care were assessed to see the supportive role of the app.•Some patients reported low health literacy running a risk of poorer health outcomes.•Advanced health literacy skills improved with the support of the app. Patients’ ability to self-monitor symptoms and engage in self-care activities is dependent upon their level of health literacy. Health literacy and self-care ability was compared in men with prostate cancer undergoing radiotherapy that used an app for symptom management with a control group. Included were an intervention group (n = 66), who used an app for symptom reporting and support for self-care, and a control group (n = 64). Outcomes were Functional Health Literacy, Communicative and Critical Health Literacy and Appraisal of Self-Care Agency (ASA-A). The intervention group had improved regarding “ability to select information needed from a variety of information sources” (p = .020), “ability to determine the information credible” (p = .041), and “being able to plan and decide what to do to improve health” (p = .004). No inter-group difference was found for ASA-A. With the support of an app for reporting and managing symptoms, important advanced health literacy skills of selecting, determining, and judging information credible may improve. Patients undergoing treatment for prostate cancer may benefit from an individualized approach, such as an app, for communication with health care providers and as a source of health information to make decisions about their own health.