Smartphone technology similar to that used in GPS systems could be used to determine cannabis intoxication, according to US researchers.
The study by New Jersey’s Rutgers Institute for Health, Health Care Policy and Ageing Research evaluated the feasibility of using smartphone sensor data to identify episodes of cannabis intoxication in the natural environment.
It found a combination of time features (time of day and day of week) and smartphone sensor data had a 90% accuracy rate, potentially providing an alternative to existing detection methods such as blood, urine and saliva tests.
Corresponding author and professor of psychiatry Tammy Chung said: “Using the sensors in a person’s phone, we might be able to detect when [they] might be experiencing cannabis intoxication and deliver a brief intervention… to reduce cannabis-related harm.”
The researchers analysed daily data collected from young adults using cannabis at least twice per week. They found that time of day and day of week had 60% accuracy in detecting self-reporting of cannabis intoxication while adding smartphone sensor data into the mix resulted in 90% accuracy.
Travel patterns from GPS data, at times when participants reported feeling high, and movement data from the phone’s accelerometer, were the most important in detecting self-reported cannabis intoxication.
The authors said future research should test the algorithm in less frequent users. The study was published in Drug and Alcohol Dependence.