Dr. Schueller is the Executive Director of PsyberGuide and an Assistant Professor at Northwestern University’s Feinberg School of Medicine. He is a faculty member of Northwestern’s Center for Behavioral Intervention Technologies (CBITs) and his work focuses on increasing the accessibility and availability of mental health resources through technology.
Although many researchers and academics have decried the lack of scientific evidence for many mobile apps available on the public app stores, fewer have brought up the glaring usability issues of such resources. Usability refers to how easy an app is to use. In order for a mobile health app to be useful, it must first be usable. Usability testing, that is the analysis of how well users can learn and use a product to achieve their goals and how satisfied users are with that process, has a long history in the development and evaluation of technologies. Engineers, computer scientists, and human-computer interaction specialists usually consider usability guidelines in their designs and evaluate usability as a first step in the evaluation of novel technologies. Usability testing is less frequently used in by clinical psychologists or behavioral scientists conducting research on mobile mental health apps, who often jump to evaluations of whether apps lead to intended changes in clinical outcomes (e.g., less depressed or anxious, increased well-being). Therefore, we often learn whether or not an app can be effective, without knowing how easy it is for people to use it on their own. Usability is captured in “Functionality” score on the Mobile App Rating Scale (MARS) that PsyberGuide uses to rate products listed on our site. Functionality on the MARS refers to the functioning, ease of use, navigation, flow logic, and gestural design of the app.
A recent study explored the usability of 4 mental health apps (Depression CBT, Mood Tools, Optimism, and T2 MoodTracker).1 Twenty-six patients were invited into the laboratory to complete a series of tasks on these apps and researchers watched, videotaped, and questioned participants to learn more about the usability of these apps. These tasks included data entry tasks such as entering one’s mood or taking a depression test and data retrieval tasks such as viewing a graph or watching a video. Only 51% of the time were participants able to complete the data entry tasks without assistance. Data retrieval tasks were even more challenging at 43%. Participants reported that their experiences with these apps were frustrating and instilled a lack of confidence that such tools could then be helpful for them. Not an extremely positive review of the usability of these apps.
I bring up these results as a word of warning both to those developing mobile health apps and those using mobile health apps. Developers, we can and should do better. Mobile health apps should be easy to use for a wide range of the people. The authors of this paper offered the following advice: (1) explain why each task is helpful, (2) use simple language and graphics, (3) reduce the number of screens, and (4) reduce manual entry as much as possible. And for those who want to use mobile health apps, this is one reason we provide multiple ratings of mental health apps on our website. PsyberGuide ratings address the credibility of a product. MARS ratings combine several aspects of an app, including its functionality. Lastly, expert reviews provide detailed information about why and how an app might be beneficial for you. An app might have a lot of research support, and thus a high PsyberGuide rating, but low scores for engagement, functionality, and aesthetics and thus a low MARS score. Usability and functionality might be a more important aspect for particular people. For designers, we need to better understand the capacities of the people we’re designing for. For users, it’s helpful to have a sense of your own capabilities with mobile technology and to select an app that best fits with those capabilities. If you’re having trouble using a mobile app, you’re not alone and it might be useful to run it by someone you trust – a doctor, family member, friend, to see if they can help you figure it out. And remember that for you to benefit from a mobile app, you need to use it, and one of our tasks at PsyberGuide is to help you find which apps are most usable.
- Sarkar, U., Gourley, G. I., Lyles, C. R., Tieu, L., Clarity, C., Newmark, L., … & Bates, D. W. (2016). Usability of commercially available mobile applications for diverse patients. Journal of general internal medicine, 31(12), 1417-1426. https://www.ncbi.nlm.nih.gov/pubmed/27418347