Objective: Design and evaluation of the dietary intake monitoring application (DIMA) to assist varying-literacy patients receiving hemodialysis to adhere to their prescribed dietary regimen.
Methods: An iterative, user-centered design process informed by Bandura's social cognitive theory was employed to design DIMA--a mobile application that utilizes touch-screen, visual interfaces; barcode scanning; and voice recording to assist varying-literacy patients receiving hemodialysis to self-monitor their diet. A pilot field study was conducted where 18 patients receiving hemodialysis were recruited face-to-face from two dialysis facilities to use DIMA for 6 weeks. Subjects recorded their dietary intake using DIMA and met with research assistants three times each week. All interactions with DIMA were logged. Subjects' interdialytic weight gain was recorded throughout the study. At the end of the study, two face-to-face questionnaires were administered to assess usability and context of use.
Results: Subjects were able to use DIMA successfully--12 subjects used DIMA as much or more at the end of the study as they did at the beginning and reported that DIMA helped them change their diet. Subjects had difficulty using the barcode scanner. Viewing past meals was the most used of the reflection mechanisms in DIMA.
Conclusion: Results suggest that while many design features were useful, some could be improved. In particular, future versions of DIMA will be on a smartphone using a camera for barcode scanning, integrate feedback and past meal reflection into the normal flow of the application, and support visual cues when selecting food items.