The Ned case study is a 12-month mixed methods embedded single-case study with a nested within-group pre-post comparison of health outcomes. 400 patients, 200 caregivers, and 10 clinicians will be given access to Ned. Participants will be asked to complete study assessments at baseline, 2 months, 6 months and 12 months. 30 semi-structured qualitative interviews with patients (n=20) and their caregivers (n=10) post-study will also be conducted to gain insight into their experience with the application.

By 2030, prostate cancer will be the most commonly diagnosed cancer in North America. To mitigate this impending challenge, comprehensive support mechanisms for disease and treatment-specific changes in health and wellbeing must be proactively designed and thoughtfully implemented for streamlined survivorship care. Mobile health applications have been lauded as a promising complement to current outpatient treatment and monitoring strategies, but have not yet been widely used to support prostate cancer survivorship needs. A realist evaluation is needed to examine the impact of such applications on the prostate cancer survivorship experience.

The investigators seek to gain an understanding of how a mobile health application for prostate cancer survivorship care called Ned ("No Evident Disease") is adopted and accepted by patients, caregivers and clinicians. The investigators also aim to determine the effect of Ned on health-related quality of life, satisfaction with cancer care, unmet needs, self-efficacy, and prostate cancer-related levels of anxiety.

The Ned case study is a 12-month mixed methods embedded single-case study with a nested within-group pre-post comparison of health outcomes. 400 patients, 200 caregivers, and 10 clinicians will be given access to Ned. Participants will be asked to complete study assessments at baseline, 2 months, 6 months and 12 months. 30 semi-structured qualitative interviews will be conducted with patients (n=20) and their caregivers (n=10) post-study to gain insight into their experience with the application.

This will be the first realist case study to evaluate an application for prostate cancer survivorship care. Prostate cancer survivors are set to increase in number and longevity, heightening the need for integrated survivorship solutions to provide them with optimal and durable outcomes. The knowledge gained from this study will comprehensively inform how and why Ned works, for whom, and in what circumstances. Understanding the impact of digital health interventions like Ned on how survivors care for themselves is critical to realising patient-centered care.

Patients must meet the following eligibility criteria to be enrolled into the study:

• 18 years of age or older
• Receiving care at the THP Mississauga Hospital or Credit Valley Hospital
• Pathology report confirming prostate cancer diagnosis via transrectal, transperineal or transurethral biopsy (standard 12-core template)
• Life expectancy > 1 year
• No concomitant cancer diagnosis
• Own a device that is compatible with the Ned application and is web-enabled through a data plan and/or wifi capabilities (e.g. laptop, desktop, tablet, smartphone)
• Able to read, write and speak English