User-centered development of an mHealth app for cardiovascular prevention

Figures

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  Figure 1.. Personas and their potential requirements identified during HerzFit´s design thinking phase.

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  Figure 2.. Connecting HerzFit with Apple Health/HealthKit for automatic synchronization of sensor data.

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  Figure 3.. Core modules of the HerzFit app. The HerzFit app is divided into four core modules: two modules for assessing cardiovascular risk and monitoring health parameters (“Measure”), one module for lifestyle modification (“Improve”), and one module for information about cardiovascular health and disease (“Learn”). The profile area allows users to manage their profile settings and upload documents.

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  Figure 4.. Top-level design of the HerzFit system. The HerzFit app gathers health and lifestyle data and receives content and information from the content management system.

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  Figure 5.. Herzfit usability testing. Boxplots of the results of the HerzFit usability testing, representing the two used questionnaires System Usability Scale (SUS) and German mHealth App Usability Questionnaire (GER-MAUQ) including its three subscales Ease of Use (GER-MAUQ_Q), Interface and Satisfaction (GER-MAUQ_I), and Usefulness (GER-MAUQ_U). With an average SUS score of 68.1 (median 70.0 ± 18.8) and an average GER-MAUQ score of 4.5 (median 4.6 ± 1.4) HerzFit´s usability was rated as above average. In the subscale analysis, HerzFit showed an above-average performance in Ease of Use (GER-MAUQ_E) and Interface and Satisfaction (GER-MAUQ_I), and an average performance in Usefulness (GER-MAUQ_U). The average ratings for both scales are represented by the red lines.