JMIR Publications

ABSTRACT

Background:

Digital health technologies are increasingly used to support exercise and frailty prevention among older adults. Although usability, technology acceptance, and user experience are commonly assessed, it remains unclear whether these assessments correspond to sustained adherence to the health behaviour supported by the technology.

Objective:

This study examined whether commonly used assessments of usability, technology acceptance, and user experience corresponded to sustained adherence to a prescribed exercise program over 6 months and explored additional factors that might help explain differences in adherence trajectories.

Methods:

An explanatory sequential mixed-methods design was used in a pilot implementation of the POSITIVE digital health system at a primary health care centre in Stockholm, Sweden. The pilot was conducted within the EU-funded POSITIVE project. Nine older adults who completed the six-month intervention and all end-of-intervention assessments were included in the present analysis. Longitudinal adherence to an individualised exercise programme was examined over six months. At the end of the intervention, participants completed the System Usability Scale (SUS), a Technology Acceptance Model (TAM) questionnaire, and the User Experience Questionnaire (UEQ), and participated in semi-structured interviews. Exploratory Spearman rank-order correlations were used to examine associations between six-month adherence and technology assessment scores. Individual adherence trajectories were then examined in relation to qualitative interview findings.

Results:

Participants showed substantial variation in both adherence level and trajectory. Five descriptive adherence profiles were identified: low and stable, moderate and increasing, moderate and decreasing, high and decreasing, and high and stable adherence. Exploratory associations between 6-month adherence and SUS, TAM, and UEQ scores were generally positive but did not provide a consistent explanation of individual adherence patterns. Qualitative findings indicated that the digital system primarily provided structure for exercise, including scheduling, completion tracking, and progress monitoring, rather than acting as the primary source of motivation. Personal motivation established exercise habits, physical circumstances, perceived fit of the prescribed exercises, technical reliability, and preferences for autonomy and flexibility appeared to contribute to differences in adherence trajectories.

Conclusions:

Standardised assessments of usability, technology acceptance, and user experience provided useful information about participants' perceptions of the digital technology but did not fully correspond to sustained adherence to the supported exercise program. Longitudinal adherence measures combined with qualitative assessment may provide a more comprehensive understanding of sustained engagement with digital health-supported interventions in older adults.