Category: Technology
Objective: To define i) the minimally required daily wear time during waking hours that constitutes a valid measurement of walking using digital mobility outcomes (DMOs) in people with Parkinson’s disease (PD); ii) the minimal number of valid measurement days and iii) valid weekend days that are required to obtain reliable weekly walking activity measures.
Background: Walking impairment is an important risk factor for falls, hospitalizations and mortality in people with PD. Yet, guidelines still have to be defined for obtaining valid and reliable walking activity (e.g., number of steps per day) and gait (e.g., walking speed in short (10 – 30 s) walking bouts) derived from wearable sensors worn in the real world.
Method: In the EU-funded IMI Mobilise-D study, people with PD were asked to wear a single wearable device on the lower back for 24 hours/day for seven days. For every day, 25 walking activity outcomes and gait DMOs were calculated. Minimally required daily wear time was determined as the highest daily wear time category (>14h as reference category) that did not result in a statistically significant change in DMO values. The minimally required number of valid measurement and weekend days were defined by an Intraclass correlation coefficients >0.80.
Results: 3466 days from 542 people with PD (Hoehn & Yahr stage I (17%), II (68%) and III (15%)) were analysed. The minimally required daily wear time varied between “no minimal requirement” and >14 hours (Table 1). The minimally required number of valid measurement days varied between one day and more than seven days. Of note, longer walking bouts (of which there were fewer) and walking bout variability needed more than seven days to be reliable. The number of included weekend days did not affect the reliability of the DMOs.
Conclusion: Minimally required wear time and number of valid days were DMO-specific, but did not differ for week or weekend days. Overall, we recommend to aim for a minimal wear time during waking hours of >12 hours for ≥ four days. However, depending on the goal of measurement and primary outcome chosen, this could be longer or shorter.
Table 1
To cite this abstract in AMA style:
J. Buekers, J. Marchena, S. Koch, J. Lemos, J. Cherdova, C. Becker, T. Bonci, J. Braun, B. Caulfield, A. Frei, E. Gazit, J. Hausdorff, A. Mirelman, S. Del Din, L. Alcock, A. Yarnall, C. Jansen, M. Long, B. Sharrack, D. Singleton, C. Schlenstedt, W. Maetzler, H. Gassner, A. Ionescu, P. Ginis, A. Nieuwboer, L. Rochester, J. Garcia-Aymerich. Reliability of real-world walking activity and gait assessment in people with Parkinson’s disease – how many hours and days are needed? [abstract]. Mov Disord. 2024; 39 (suppl 1). https://www.mdsabstracts.org/abstract/reliability-of-real-world-walking-activity-and-gait-assessment-in-people-with-parkinsons-disease-how-many-hours-and-days-are-needed/. Accessed June 15, 2025.« Back to 2024 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/reliability-of-real-world-walking-activity-and-gait-assessment-in-people-with-parkinsons-disease-how-many-hours-and-days-are-needed/