When you need to test if you are running a fever, you may not have an accurate at-home thermometer handy. However, many people may have the next best thing right in their pocket — a smartphone.
A team of researchers in the Allen School’s UbiComp Lab and UW School of Medicine developed the app FeverPhone that turns smartphones into thermometers without the need for additional hardware. The research, which was originally published in the Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies, received an IMWUT Distinguished Paper Award at the ACM International Joint Conference on Pervasive and Ubiquitous Computing/International Symposium on Wearable Computing (UbiComp/ISWC) in Melbourne, Australia, in October.
“It feels great to have this work spotlighted by the community like this because it brings light to the still unexpected utility inside these — already ubiquitous — devices,” lead author Joe Breda, a Ph.D. student in the Allen School, said. “I like to do this type of research as it demonstrates what can be done with the sensor hardware already in people’s pockets so the next generation of devices might include these kinds of techniques by default. This is particularly important for applications like health sensing where ensuring access to diagnostics at the population scale can have serious impacts.”
The app is the first to use smartphones’ existing sensors to gauge whether or not someone has a fever. Inside most off-the-shelf smartphones are small sensors called thermistors that monitor the temperature of the battery. These sensors happen to be the same ones clinical-grade thermometers use to estimate body temperature. The researchers found that the smartphone’s touchscreen could sense skin-to-phone contact, while the thermistors could estimate the air temperature and the rise in heat when the phone was pressed against someone’s forehead.
The team tested out FeverPhone’s temperature-sensing capabilities against a traditional oral thermometer on patients at the UW School of Medicine’s Emergency Department. FeverPhone’s readings were within the clinically acceptable range. Although the app still needs more testing before it can be widely used, FeverPhone’s potential to help during sudden times of demand when thermometers may be less available is still exciting for doctors.
“People come to the ER all the time saying, ‘I think I was running a fever.’ And that’s very different than saying ‘I was running a fever,’” said study co-author Mastafa Springston, M.D., in a UW News release. “In a wave of influenza, for instance, people running to the ER can take five days, or even a week sometimes. So if people were to share fever results with public health agencies through the app, similar to how we signed up for COVID exposure warnings, this earlier sign could help us intervene much sooner.”
Since the team published the paper last year, some smartphone makers have introduced their own body temperature sensors.
“For example, it’s not unlikely that this paper directly inspired Google Pixel to introduce this new functionality, which was exactly why I pursued this work in the first place,” Breda said. “I wanted to advocate for these big tech companies to consider minimal hardware or software changes to these ubiquitous devices to make health care more accessible. I actually met with someone on the team shortly after this work was submitted to share my findings.”
Breda has turned his attention toward other devices with potential health care capabilities. For example, he is currently researching how smartwatches can be used for early detection of influenza-like illnesses. Breda has been collaborating with the National Institutes of Health (NIH) to build models that can passively detect if the wearer is getting sick, starting on the first day of virus exposure, using signals from their heart rate, temperature and skin conductance. Last October, he traveled to Washington, D.C. to test the technology on patients at the NIH.
“In the next phase of my career, I am looking at how ubiquitous computing and artificial intelligence-powered sensing on these devices can improve public health through analyzing biomarkers for disease prevention, and even more broadly through improving urbanism and digital civics,” Breda said. “These devices offer a unique opportunity to detect, or in some cases even predict, personal and public health issues before they even happen.”
Breda and Springston’s co-authors on the award-winning paper include Shwetak Patel, the Washington Research Foundation Entrepreneurship Endowed Professor in the Allen School and UW Department of Electrical & Computer Engineering, and Allen School alum Alex Mariakakis (Ph.D., ‘19), a professor at the University of Toronto.
Read the FeverPhone research paper here, the UW News release here and a related Gizmodo article here.