SEATTLE – Scientists and engineers from the University of Washington have developed a mobile app to screen for anemia that has high accuracy rates.
“The ability to screen quickly with a smartphone-based test could be a huge improvement to delivering care in limited-resource environments,” said Doug Hawkins, who co-authored a paper outlining the technology.
The team of authors presented the paper recently at the Association for Computing Machinery’s 2016 International Joint Conference on Pervasive and Ubiquitous Computing in Germany.
By shining light from a smartphone’s camera flash through a patient’s finger, HemaApp analyzes the color of his or her blood to estimate hemoglobin concentrations. The app bombards the finger with different wavelengths of light and infrared energy and creates a series of videos. By analyzing how colors are absorbed and reflected across those wavelengths, it can detect concentrations of hemoglobin and other blood components like plasma.
Processing algorithms that account for various skin tones and body masses use the patient’s pulse to distinguish between the patient’s blood and the physical characteristics of his or her finger.
Newer smartphones are beginning to have more advanced infrared and multi-color LED capabilities, but Professor Shwetak Patel said even if a phone didn’t have those capabilities, “you can put your finger near an external light source like a common light bulb and boost accuracy rates.”
While the app is not intended to replace blood tests, which are the most accurate way to measure hemoglobin, in initial trials, HemaApp’s hemoglobin measurements had a 69% correlation to a patient’s Complete Blood Count test using a smartphone camera alone, a 74% correlation when used under a common incandescent light bulb, and an 82 % correlation when using a small circle of LED lights that can snap onto the phone.
Researchers said that HemaApp can be an effective and affordable initial screening tool to determine if further blood testing is warranted, which would be done the traditional way with a needle.
“It would be really nice to not have to perform a procedure every time we want to answer that question,” said researcher Terry Gernsheimer.
HemaApp will be tested on a wider national and international audience. Researchers will also investigate whether smartphones can be used to help screen for other blood disorders.
“There’s a lot we want to tackle in using phones for non-invasively screening disease,” said Patel.