Table 6.
Impact of design choices on usability and engagement.
| Design feature (modality and engagement of completers) | Intended function | Positive user feedback | Negative user feedback | Effectiveness and recommendations |
| Chatbot interactions (mobile; mandatory component; engaged completers: n=57, 100%) | Support structured self-monitoring and lifestyle reflection | It was valued for its ease of use, usefulness, motivational impact, and ability to create awareness. In addition, habit formation, such as integrating it into daily routines (eg, notification timing aligned with personal schedule), was appreciated. | It was perceived as repetitive, complex (specifically with respect to nutrition), and difficult to correct, leading to reduced engagement over time. Users occasionally forgot to respond to prompts, and stress-related questions felt redundant. | Needs adaptive personalization to maintain engagement. |
| Health watch (device; mandatory component; engaged completers: n=57, 100%) | Passive lifestyle tracking (eg, heart rate, activity, and sleep) | It was valued for its heart rate insights, step tracking, motivational impact, sleek design, ease of use, and overall usefulness. | Frustration arose from technical issues, including synchronization failures, measurement inaccuracies, and short battery life. | Ensure technical reliability and offer alternative device options. |
| Quarterly lifestyle self-assessment via the dashboard (desktop web application; mandatory component; engaged completers: n=57, 100%) | Self-assessment tool for cardiovascular risk behaviors and providing feedback via the dashboard | It was valued for its immediate results and comprehensiveness, as well as the (sometimes strict) feedback and advice provided at the end of the questionnaires. | Limited accessibility due to desktop-only version. Questionnaires were lengthy but manageable. | Improve accessibility by offering mobile version. |
| Lifestyle dashboard (desktop web application; engaged completers: n=32, 58%) | Encourage behavior change through reflecting on self-monitoring insights | It was valued for useful nutritional advice (indication of healthiness per food item) and other health insights. | Limited accessibility (desktop only) and absence of real-time feedback reduced usability. | AIa-driven dynamic feedback could enhance engagement. Users expressed a desire to compare their health status with normative data for their patient group. Improving accessibility through a mobile app is recommended. |
| Goal-setting functionality (optional; desktop web application; engaged completers: n=4, 7%) | Allow users to set and track personal lifestyle goals | Gave motivation to set own goals or positively adjust goals (eg, increased steps). | Limited engagement due to lack of guidance and complexity. | Offer clearer instructions and integrate automated, personalized goal recommendations to improve usability. |
| Sharing functionality (optional; desktop web application; engaged completers: n=0, 0%) | Enable users to share collected lifestyle data via the platform with relatives or health care professionals | —b | No engagement due to lack of guidance, lack of perceived benefit, and privacy concerns. | Provide clearer use cases, privacy assurances, and user education on potential benefits. |
aAI: artificial intelligence.
bNot applicable.