Your smartphone can do everything from tracking the amount of steps you take daily to reminding you to call your mother, but can a phone actually tell if you’re depressed? Researchers at Northwestern Medicine believe so. Using sensor data from your smartphone to track the number of minutes you use your phone and your different geographical locations, a new study is finding that your phone may be key to diagnosing your mental health.

Growing research is showing that the more time you spend on your phone, the more likely it is that you are depressed. Research conducted by Baylor University found that frequent cell phone use was often associated with a need to improve mood. After examining 346 college students, researchers found those that were addicted to their gadgets also displayed characteristics of moodiness, materialism, and temperamental behavior — all symptoms attributed to depression. What’s more, researchers from Northwestern Medicine previously found that depressed individuals tend to use their phones for an average of 68 minutes per day, while individuals without depression use their phones for only 17 minutes each day.

Most researchers believe that frequent phone use is also another form of retreating from the public sphere, a characteristic often attributed to those suffering from depression. To go along with this, researchers are examining the amount of places phone users spend their time, finding that those who travel to fewer locations daily, preferring to stay at places like home, may be depressed.

“The data showing depressed people tended not to go many places reflects the loss of motivation seen in depression,” said David Mohr, of Northwestern University's Feinberg School of Medicine, in a recent press release. “When people are depressed, they tend to withdraw and don’t have the motivation or energy to go out and do things.”

Northwestern scientists are thus working to track the two, creating an algorithm on smartphones that can track the overall time of phone usage, along with the variety of geographic locations a person travels to. In doing this, researchers have found they can identify if a person has depression with a stunning 87 percent accuracy. They have published their findings in the Journal of Medical Internet Research.

“The significance of this is we can detect if a person has depressive symptoms and the severity of those symptoms without asking questions,” Mohr said. “We now have an objective measure of behavior related to depression. And we’re detecting it passively. Phones provide data unobtrusively and with no effort on the part of the user.”

Researchers hope that utilizing phones in this way will eventually help health care professionals stage interventions for those not seeking help. They also believe the data that can be collected from smartphones is more telling than the surveys they gave to participates asking how sad they felt on a scale of 1 to 10. These answers can occasionally be dishonest and unreliable, says lead author Sohrob Saeb, a postdoctoral fellow and computer scientist in preventive medicine at Feinberg.

Researchers were not able to track the types of activities depressed individuals were using their phones for, but Mohr believes that they are most likely surfing the web or playing games to avoid social interactions. “People are likely, when on their phones, to avoid thinking about things that are troubling, painful feelings, or difficult relationships,” he says. “It’s an avoidance behavior we see in depression.”

To test the efficacy of using data tracking to diagnose depression, researchers examined the GPS locations and phone usage of 28 people, who were an average of 29 years old, for two weeks. The GPS sensors vigilantly tracked locations every five minutes.

In order to have a basis to compare their results to, researchers asked participants to take the PHQ-9 at the beginning of the two-week study; the PHQ-9 is a widely accepted questionnaire most often used to measure depression by examining sadness, loss of pleasure, hopelessness, and difficulties eating, sleeping or concentrating. Along with the results of the PHQ-9, researchers created an algorithm using the phone’s GPS and data usage tracker to detect the person’s whereabouts, and how often they touched their screens. These results were then compared with the test results.

Ultimately, researchers found that out of the 28 participants, 14 showed no signs of depression while the remaining 14 showed symptoms of mild to severe depression. These results were consistent with test results.

Scientists from Northwestern believe that this novel utilization of smartphones can help passively detect emotional states of individuals, and eventually allow for better, more immediate care. They plan on examining whether changing the habits that they studied improves overall mood. “We will see if we can reduce symptoms of depression by encouraging people to visit more locations throughout the day, have a more regular routine, spend more time in a variety of places, or reduce mobile phone use,” concluded Saeb.

Source: Saeb S, Mohr D, et al. Journal of Medical Internet Research. 2015.

Roberts J, Pullig C, Manolis C, et al. I need my smartphone: A hierarchical model of personality and cell-phone addiction. Elsevier. 2015.