Drinking or driving? The choice is yours. However, in the near future, your smartphone may be able to decide for you, according to a study conducted by a group of researchers from the US universities of Stanford and Pittsburgh, which has been published in the "Journal of Studies on Alcohol and Drugs."
The study involved 22 adult volunteers, who drank enough vodka to reach a blood-alcohol level of 0.2 percent, which is well in excess of the 0.08 percent maximum allowed for drivers in the United States. Thereafter, they completed a series of exercises monitored by the mobile application phyphox, which accessed data from the triple axis accelerometer in a smartphone attached to their belts.
As to the method: before drinking the participants were asked to walk ten steps in a straight line and then to turn and walk ten steps back.
Accelerometer data from this baseline test was then compared with seven further hourly iterations of the same exercise after participants had been served vodka. Participants' levels of blood alcohol were also checked after each of the exercises.
The researchers discovered that the phone's accelerometer was capable of detecting changes in gait caused by inebriation with an accuracy of 92.5 percent. They also found that walking in a drunken manner was a very reliable indicator of intoxication. Further experiments have now been planned to see if it is possible to obtain even more precise results.