Digital Phenotyping and Digital Interventions in Adolescent and Young Adult Cancer Survivors Long-Term Follow-up: A Scoping Review (Preprint)

BACKGROUND As survival after adolescent and young adult (AYA) cancer continues to improve, follow-up care needs to address late effects, psychosocial challenges, and quality-of-life impacts after treatment. Conventional follow-up models remain largely episodic and may miss fluctuations in symptoms, functioning, and everyday well-being. Digital phenotyping can capture real-world health-related patterns through smartphones, wearables, apps, sensors, and patient-generated health data, while digital interventions can translate these data into feedback, self-management support, behavioral or psychosocial intervention content. However, how these approaches are used in AYA survivorship follow-up, and which user-oriented factors facilitate or limit their adoption and sustained use, remains fragmented. OBJECTIVE This scoping review aimed to map user-oriented evidence on digital phenotyping and digital interventions in post-treatment AYA cancer survivorship follow-up, focusing on technologies, support strategies, and the facilitators and barriers influencing adoption and use. To our knowledge, this is the first review to examine digital phenotyping and digital interventions together in post-treatment AYA cancer follow-up from a user-oriented perspective. METHODS The review followed PRISMA-ScR guidance. Searches were conducted in PubMed, Web of Science, Scopus, and PsycNet, with SciSpace as a supplementary AI-assisted discovery tool. Peer-reviewed English-language publications from 2020 to early 2026 were eligible when they focused on AYA cancer survivors, digital phenotyping or digital interventions, and user-oriented outcomes. Data were extracted using structured tables and synthesized thematically. RESULTS Sixteen publications were included. Digital follow-up was organized through complementary support strategies: adaptive goal setting, tailored feedback, personalized coaching, peer or social connectivity, and clinical integration. No publication relied on passive sensing alone. Collected data were mainly used for self-monitoring, less often to adapt goals, feedback, or risk information, and rarely connected to clinical follow-up. Wearable data supported mainly physical activity, while psychosocial and sleep support relied more on self-report and human interaction. Seventy-seven facilitator examples were grouped into 11 themes, most frequently engagement, social support integration, personalization and adaptive design, user experience, and benefits. Barriers were most frequently related to personalization and adaptive design, engagement, timing of activities, and technical support or issues. CONCLUSIONS Digital follow-up in AYA cancer survivorship is developing from isolated monitoring or intervention components toward service processes that connect monitored information with feedback, self-management support, and follow-up care where available. Acceptable digital support depends on manageable engagement, personalization, relational support, visible benefit, usable and accessible interaction, technical reliability, and clear privacy and data-control conditions. These facilitators and barriers can be translated into requirement areas, specified through stakeholder elicitation and co-design, and used to evaluate digital follow-up systems in practice.