Smartphones may be able to detect depression by tracking the number of minutes they're in use as well as an owner’s geographical locations, according to a Northwestern University study.

The research is based on reviews of phone use that have shown the more time you spend using your phone, the more likely you are to depressed, Medical Xpress reports.

The average daily usage for depressed individuals was about 68 minutes, while for non-depressed individuals it was about 17 minutes, the researchers found.

In addition, spending most of your time at home or in fewer locations — as measured by GPS tracking — is also linked to depression. In addition, having a less regular day-to-day schedule may flag depression risks.

Lead researcher David Mohr, director of the Center for Behavioral Intervention Technologies at Northwestern University Feinberg School of Medicine, said scientists were able to identify people with depressive symptoms with 87 percent accuracy, using the phone-tracking technique.

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

The research could ultimately lead to monitoring people at risk of depression and enabling healthcare providers to intervene more quickly, said the researchers, who reported their findings in the Journal of Medical Internet Research.