A Novel System for the Device-Based Measurement of Physical Activity, Sedentary Behavior, and Sleep (Motus): Usability Evaluation

Patrick Crowley; Rasmus Kildedal; Simon Overvad Vindelev; Sandra Schade Jacobsen; Jon Roslyng Larsen; Peter J Johansson; Mette Aadahl; Leon Straker; Emmanuel Stamatakis; Andreas Holtermann; Paul Jarle Mork; Nidhi Gupta

doi:10.2196/48209

A Novel System for the Device-Based Measurement of Physical Activity, Sedentary Behavior, and Sleep (Motus): Usability Evaluation

JMIR Form Res. 2023 Nov 17:7:e48209. doi: 10.2196/48209.

Authors

Affiliations

¹ The National Research Centre for the Working Environment, Copenhagen, Denmark.
² Department of Medical Sciences, Occupational and Environmental Medicine, Uppsala University, Uppsala, Sweden.
³ Occupational and Environmental Medicine, Uppsala University Hospital, Uppsala, Sweden.
⁴ Center for Clinical Research and Prevention, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark.
⁵ Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
⁶ School of Allied Health, Curtin University, Perth, Australia.
⁷ Charles Perkins Centre, Mackenzie Wearables Research Hub, University of Sydney, Sydney, Australia.
⁸ School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
⁹ Department of Public Health and Nursing, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway.

PMID: 37976096
PMCID: PMC10692873
DOI: 10.2196/48209

Abstract

Background: Device-based measurements of physical behavior, using the current methods, place a large burden on participants. The Motus system could reduce this burden by removing the necessity for in-person meetings, replacing diaries written on paper with digital diaries, and increasing the automation of feedback generation.

Objective: This study aims to describe the development of the Motus system and evaluate its potential to reduce participant burden in a two-phase usability evaluation.

Methods: Motus was developed around (1) a thigh-worn accelerometer with Bluetooth data transfer; (2) a smartphone app containing an attachment guide, a digital diary, and facilitating automated data transfer; (3) a cloud infrastructure for data storage; (4) an analysis software to generate feedback for participants; and (5) a web-based app for administrators. We recruited 19 adults with a mean age of 45 (SD 11; range 27-63) years, of which 11 were female, to assist in the two-phase evaluation of Motus. A total of 7 participants evaluated the usability of mockups for a smartphone app in phase 1. Participants interacted with the app while thinking aloud, and any issues raised were classified as critical, serious, or minor by observers. This information was used to create an improved and functional smartphone app for evaluation in phase 2. A total of 12 participants completed a 7-day free-living measurement with Motus in phase 2. On day 1, participants attempted 20 system-related tasks under observation, including registration on the study web page, reading the information letter, downloading and navigating the smartphone app, attaching an accelerometer on the thigh, and completing a diary entry for both work and sleep hours. Task completion success and any issues encountered were noted by the observer. On completion of the 7-day measurement, participants provided a rating from 0 to 100 on the System Usability Scale and participated in a semistructured interview aimed at understanding their experience in more detail.

Results: The task completion rate for the 20 tasks was 100% for 13 tasks, >80% for 4 tasks, and <50% for 3 tasks. The average rating of system usability was 86 on a 0-100 scale. Thematic analysis indicated that participants perceived the system as easy to use and remember, and subjectively pleasing overall. Participants with shift work reported difficulty with entering sleep hours, and 66% (8/12) of the participants experienced slow data transfer between the app and the cloud infrastructure. Finally, a few participants desired a greater degree of detail in the generated feedback.

Conclusions: Our two-phase usability evaluation indicated that the overall usability of the Motus system is high in free-living. Issues around the system's slow data transfer, participants with atypical work shifts, and the degree of automation and detail of generated feedback should be addressed in future iterations of the Motus system.

International registered report identifier (irrid): RR2-10.2196/35697.

Keywords: accelerometer; accelerometry; app; application; design; development; diary; exercise; mhealth; mobile health; monitor; monitoring; physical activity; sedentary; sleep; thematic analysis; usability.

©Patrick Crowley, Rasmus Kildedal, Simon Overvad Vindelev, Sandra Schade Jacobsen, Jon Roslyng Larsen, Peter J Johansson, Mette Aadahl, Leon Straker, Emmanuel Stamatakis, Andreas Holtermann, Paul Jarle Mork, Nidhi Gupta. Originally published in JMIR Formative Research (https://formative.jmir.org), 17.11.2023.