Dr Phone

Your smartphone may well do some things better than a human doctor:

A smartphone application using the phone's camera function performed better than traditional physical examination to assess blood flow in a wrist artery for patients undergoing coronary angiography, according to a randomized trial published in CMAJ (Canadian Medical Association Journal).

These findings highlight the potential of smartphone applications to help physicians make decisions at the bedside. "Because of the widespread availability of smartphones, they are being used increasingly as point-of-care diagnostics in clinical settings with minimal or no cost," says Dr. Benjamin Hibbert of the University of Ottawa Heart Institute, Ottawa, Ontario. "For example, built-in cameras with dedicated software or photodiode sensors using infrared light-emitting diodes have the potential to render smartphones into functional plethysmographs [instruments that measure changes in blood flow]."

The researchers compared the use of a heart-rate monitoring application (the Instant Heart Rate application version 4.5.0 on an iPhone 4S) with the modified Allen test, which measures blood flow in the radial and ulnar arteries of the wrist, one of which is used to access the heart for coronary angiography. A total of 438 participants were split into two groups; one group was assessed using the app and the other was assessed using a gold-standard traditional physical examination (known as the Allen test). The smartphone app had a diagnostic accuracy of 94% compared with 84% using the traditional method.