iPhone app accurately estimates lung air volume

WASHIGTON – Researchers at the University of Washington (UW) have developed an iPhone app able to accurately estimate lung air volume. In a study involving 52 individuals, the SpiroSmart app was able to measure lung air volume within 5.1% accuracy of a commercial spirometer.

The UW researchers modeled the trachea and vocal tract and developed an algorithm that was able to translate audio recordings of breathing to an accurate estimate of an individual’s lung air volume. The system was tested using an iPhone 4S smartphone and its built-in microphones.

Spirometers are commonly used to help physicians diagnose and track the progress of various lung conditions, such as asthma, cystic fibrosis, and chronic bronchitis. Commercial portable spirometers cost thousands of dollars. Thus, development of this kind of technology may eventually lead to cheaper alternatives that can deliver accuracy that can match that of commercial spirometers at present.