A functionality design framework for elderly-centric digital self-management systems to enhance older adults’ motor health

Abstract

With ageing, individuals commonly experience motor degradation, reducing independence and quality of life. Advanced technologies have accelerated the development of digital healthcare solutions, enabling older adults to self-manage their motor health. Previous research on digital self-management systems mainly focused on single functionality, such as assessments or sensor-based exercises. Few have combined diverse functionalities to develop optimal designs that enhance motor health and confidence in older adults. Moreover, previous studies highlighted the systems' usability but ignored users' desirability, leading to abandonment or rejection. Consequently, a limited framework has been developed to guide the elderly-centric design of digital self-management systems. To improve the accessibility and usability of digital self-management systems and enhance older adults' motor health, this research developed a functionality design framework based on macroergonomic analysis and design methods. Firstly, literature reviews were used to synthesise digital self-management systems and their design frameworks. Cross-sectional surveys and semi-structured interviews with older adults and physiotherapists further explored their obstacles, perceptions, and needs regarding digital self-management of motor health. Based on the motor health self-management situation analysis and the root definition of functionality structure, an initial functionality design framework for the elderly-centric digital self-management systems was developed. A digital self-management system was then designed and tested via usability test and a pilot randomised controlled trial, validating the feasibility of the framework. The results led to further enrichment of the framework. The results showed that older adults reported positive attitudes towards education, evaluation and exercise functionalities. Perceived vulnerability, perceived severity, maladaptive response rewards, response costs, perceived ease of use, and task-technology fit significantly influence older adults' behavioural intention to use digital self-management systems. Functions including data collection, analysis, updates, feedback, info search, and activity reminders were also presented to influence older adults' behavioural intention. Additionally, physiotherapists provided valuable insights in combining optical sensors and wearable inertial sensors with the three-meter timed up and go test, five sit-to-stand test, and Berg balance test to capture older adults' lower back, knee, and foot motions. Stretching, aerobic exercise, strength, balance, and functional task training were suggested as exercises in digital self-management systems. A functionality design framework was thus developed, identifying education, evaluation, and exercise functionalities as the fundamental structure, while considering their content, technology, and material design strategies. In the usability test and pilot randomised controlled trial, older adults showed greater perceived usefulness of the designed digital system on motor health management. The system also achieved a "good" usability. The education, evaluation, and exercise functionalities all had positive effects on motor health-related outcomes (Education: handgrip strength, GSE; Evaluation: 3TUG; Exercise: 3TUG). However, each functionality presented a different effect size in diverse domains of motor health. Therefore, a comprehensive digital functionality strategy was further updated in the functionality design framework. The findings enhanced understanding of motor health management and older adults' needs for digital self-management systems. The elderly-centric functionality design framework can guide the design of accessible, usable and practical digital healthcare systems, and enhance theoretical knowledge of macroergonomics and age-centric design strategies.