Quantifying usability: an evaluation of a XXXX mHealth system on effectiveness, efficiency, and satisfaction metrics with associated user characteristics.

@entity1 @entity6 @entity8670
OBJECTIVE: Mobile health (mHealth) systems are becoming more common for chronic disease management, but usability studies are still needed on @entity1 ' perspectives and mHealth interaction performance. This deficiency is addressed by our quantitative usability study of a mHealth @entity6 system evaluating @entity1 ' task performance, satisfaction, and the relationship of these measures to user characteristics. MATERIALS AND METHODS: We used metrics in the International Organization for Standardization ( @entity8670 ) 9241-11 standard. After standardized training, 10 @entity1 performed representative tasks and were assessed on individual task success, errors, efficiency (time on task), satisfaction (System Usability Scale [SUS]) and user characteristics. RESULTS: Tasks of exporting and correcting values proved the most difficult, had the most errors, the lowest task success rates, and consumed the longest times on task. The average SUS satisfaction score was 80.5, indicating good but not excellent system usability. Data trends showed males were more successful in task completion, and younger @entity1 had higher performance scores. Educational level did not influence performance, but a more recent @entity6 diagnosis did. @entity1 with more experience in information technology (IT) also had higher performance rates. DISCUSSION: Difficult task performance indicated areas for redesign. Our methods can assist others in identifying areas in need of improvement. Data about user background and IT skills also showed how user characteristics influence performance and can provide future considerations for targeted mHealth designs. CONCLUSION: Using the @entity8670 9241-11 usability standard, the SUS instrument for satisfaction and measuring user characteristics provided objective measures of @entity1 ' experienced usability. These could serve as an exemplar for standardized, quantitative methods for usability studies on mHealth systems.
