Walking on common ground: a cross-disciplinary scoping review on the clinical utility of digital mobility outcomes

Abstract

Physical mobility is essential to health, and patients often rate it as a high-priority clinical outcome. Digital mobility outcomes (DMOs), such as real-world gait speed or step count, show promise as clinical measures in many medical conditions. However, current research is nascent and fragmented by discipline. This scoping review maps existing evidence on the clinical utility of DMOs, identifying commonalities across traditional disciplinary divides. In November 2019, 11 databases were searched for records investigating the validity and responsiveness of 34 DMOs in four diverse medical conditions (Parkinson’s disease, multiple sclerosis, chronic obstructive pulmonary disease, hip fracture). Searches yielded 19,672 unique records. After screening, 855 records representing 775 studies were included and charted in systematic maps. Studies frequently investigated gait speed (70.4% of studies), step length (30.7%), cadence (21.4%), and daily step count (20.7%). They studied differences between healthy and pathological gait (36.4%), associations between DMOs and clinical measures (48.8%) or outcomes (4.3%), and responsiveness to interventions (26.8%). Gait speed, step length, cadence, step time and step count exhibited consistent evidence of validity and responsiveness in multiple conditions, although the evidence was inconsistent or lacking for other DMOs. If DMOs are to be adopted as mainstream tools, further work is needed to establish their predictive validity, responsiveness, and ecological validity. Cross-disciplinary efforts to align methodology and validate DMOs may facilitate their adoption into clinical practice.

Mobility endpoints in marketing authorisation of drugs: what gets the European medicines agency moving?

“…In an era when smartphones and wristband wearables are being purchased in their hundreds of millions, a comprehensive assessment of mobility could include not only perception (by PROs) or capacity (by PerfO), but also objectively reflect the real-world mobility. Yet, in our analysis, we were not able to identify a single study using DMOs such as step counting, real-world walking speed or cadence [ 25 ], even when reviewing tertiary and exploratory endpoints as far as they have been reported. The inclusion of DMOs adds an objective, real-time dimension to the measurement of mobility that cannot be replaced by other clinical outcome assessments.…”

Association of clinical outcome assessments of mobility capacity and incident disability in community-dwelling older adults - a systematic review and meta-analysis

“…Walking-related digital mobility outcomes or unsupervised assessment of mobility with mobile health technologies, such as real-world walking speed recorded with wearable sensors or chair rise activities recorded with domestic-integrated devices, may overcome the limitations of conventional (supervised) COAs, such as differences between gait speed test protocols. 78,79 Moreover, digital (unsupervised) assessments of mobility appear to be more accurate and sensitive to change, and thus may emerge as complementary assessments to support risk stratification and monitoring of physical capacity of older people. 78 Methods for the non-supervised assessment of gait speed and other digital gait parameters in an older individual’s usual environment are under development.…”

Connecting real-world digital mobility assessment to clinical outcomes for regulatory and clinical endorsement – the Mobilise-D study protocol

“…However, studies are needed to establish their construct validity, predictive validity, responsiveness and clinical meaningfulness (31)(32)(33). The most recent systematic evidence (34,35) supports the need for clinical validation of DMOs within Mobilise-D. A multi-centric observational study (36) is being conducted as part of Mobilise-D to establish the technical validity and patient acceptability of the approach used to quantify digital mobility in the real-world. This technical validation study (TVS) allowed the definition of a set of procedures for the metrological verification of an inertial sensor-based device and for the experimental validation of the algorithms used to calculate the DMOs.…”