Utilization of digital mobility outcomes (DMOs) for frailty prevention and management: a scoping review

Physical frailty is a major public health issue in aging populations, contributing to functional decline and increased healthcare costs. Although the Fried phenotype is widely used for diagnosis, it relies largely on cross-sectional assessments in controlled clinical settings and may not capture day-to-day mobility changes. Digital Mobility Outcomes (DMOs), objective measures of mobility derived from wearable sensors in daily life, may address this limitation. We therefore examined their clinical and public health utility using Leavell and Clark’s three levels of prevention. Following Arksey and O’Malley’s framework and PRISMA-ScR guidelines, we searched PubMed and Google Scholar for literature published between 2015 and 2025 that examined or informed the use of DMOs in frailty-related populations. Eligible articles included empirical studies linking DMOs to clinical outcomes, as well as methodological, validation, regulatory, protocol, and implementation studies relevant to real-world mobility assessment. We identified 928 records, removed duplicates, and screened the remaining articles in two stages. Ultimately, 23 studies met the inclusion criteria. Of the 23 studies, 2 focused on primary prevention, 2 on secondary, 8 on tertiary disease management, and 11 provided foundational evidence. Across these stages, DMOs demonstrated distinct practical applications. In primary prevention, continuous tracking of physical activity supported proactive health interventions. In secondary prevention, real-world metrics (e.g., gait speed, activity patterns, and gait variability) showed promise for detecting early signs of functional decline. For tertiary prevention, DMOs were frequently used to monitor disease progression and recovery trajectories in patients with Parkinson’s disease, chronic obstructive pulmonary disease, and hip fractures. However, several barriers limit their widespread clinical adoption, including a lack of sensor and algorithmic standardization, data privacy concerns, and low technology acceptance among older adults. DMOs are promising digital biomarkers that can complement conventional clinical assessments by continuously and objectively measuring real-world mobility. Furthermore, user-centered designs are essential to ensure equitable access and prevent digital health disparities among older populations. To integrate DMOs across the frailty management continuum, future studies must prioritize robust clinical validation and institutional infrastructure. Ultimately, accumulating such evidence will facilitate proactive and personalized public health strategies for healthy aging.