- An mHealth app that pledged to easily measure one’s systolic blood pressure scored high marks with users even though the readings were inaccurate, leading researchers to question whether users value convenience over reliability.
Those observations were drawn from two separate studies of the Instant Blood Pressure app developed and marketed by California-based AuraLife in 2014. The app, which reportedly measured one’s blood pressure when the cellphone was placed against the chest with a finger, was rated as one of the top 5 apps that year, yet was also found to be inaccurate almost four out of every five times. Following a series of news stories and complaints lodged with the Federal Trade Commission, the app was removed from app stores in 2015.
In 2016, Dr. Timothy Plante, a fellow in the Division of General Internal Medicine, and Dr. Seth Martin, an assistant professor in the Division of Cardiology, both at the Johns Hopkins University School of Medicine, published a study in which the app was found to be inaccurate 77.5 percent of the time.
“Because this app does such a terrible job measuring blood pressure,” Plante said at the time, “it could lead to irreparable harm by masking the true risk of heart attacks and strokes in people who rely on the accuracy of this information.”
Fast forward to this year. In a second study recently published in npj Digital Medicine, Plante, now at the Department of Medicine at the University of Vermont in Burlington, and Martin, now at the Malone Center for Engineering in Healthcare at Johns Hopkins University in Baltimore, found that those using the app rated it highly and said they’d use it again even though it wasn’t giving them accurate information.
The two researchers returned to their earlier study of 81 people who had used the app and compared its readings against their BP estimates. They found that the better the results, the more likely users were to approve of the app and use it again.
“However, user enjoyment and likelihood of future BP monitoring were negatively associated with higher-than-expected reported systolic BP,” they reported. “These data suggest reassuring app results from an inaccurate BP-measuring app may have improved user experience, which may have led to more positive user reviews and greater sales. Systematic underreporting of elevated BPs may have been a contributor to the app’s success.”
The results of the study point to an underlying issue in mHealth app design and patient engagement – how to create a digital health platform that will not only improve clinical outcomes, but be easy enough to handle that users will continue to use it. This study suggests that users value comfort over accuracy, and might even be more inclined to use it because it gives them good news.
“For example, a theoretical app that estimates weight using a smartphone’s camera could improve enjoyment and promote a better user experience if it systematically underestimated a user’s weight and presented reassuring, lower-than-expected weight measurements to users,” Plante and Martin said. “Such an app could foster greater app use and receive positive reviews despite its inaccuracy, thereby driving uptake of this app over other, more accurate apps. However, if users perceived this app as inaccurate, they may be less likely to use it.”
This disparity is bedeviling mHealth app developers and healthcare providers looking for a way to rise above the 650,000+ apps now on the market and present a connected health platform that actually helps users improve their health.
And it challenges those looking to develop mHealth app standards to look beyond popularity as a sign of effectiveness, and to validate high-risk apps before they’re made available to the public and educate consumers on the perils of apps.
“Given the high popularity and lack of promised functionality, IBP is a prominent example of a ‘snake oil’ app that exposes its users to potential harm through poor functionality,” Plante and Martin concluded. “Understanding the reasons for the high popularity of this inaccurate app will help inform future policy development to ensure a safe app space.”