Cigarette tied in a knot

Building Apps to Help Smokers Quit

Tailored interventions delivered by smartphone may help curb smoking.

By Catherine Gara

On his way home from work, a young man walks into his favorite bar. His phone vibrates with a push notification: “Try chewing gum if you have trouble resisting smoking when others light up around you.”

Johannes Thrul is creating scenarios like this as he develops tools for smoking cessation. Citing a 2017 CDC report, Thrul says 10.4% of young adults ages 18 to 24 years old smoke cigarettes, the leading cause of preventable disease and death in the U.S. 

Thrul, PhD, an assistant professor in Mental Health, recently completed a pilot study of eight participants that tested and confirmed the feasibility of using a smartphone app to learn a person’s smoking triggers and deliver intervention messages to counteract them in real time. 

“Our earlier studies showed we can use smartphones to monitor individuals’ smoking patterns and anticipate the when and where of their high-risk situations,” says Thrul. “Now we want to use phones to deliver support when it’s most needed.”

The next phase of his study will include 160 participants. An app will record their GPS location every two minutes, and participants will report when they are smoking a cigarette. They will also receive up to seven surveys per day to provide further context: “Where are you?” “Are others present?” “Are they smoking too?” (Though it sounds burdensome, Thrul says recruiting participants hasn’t been hard.)

After two weeks of tracking, half of participants will continue being monitored as the control arm. For the other half, geofences—invisible GPS boundaries—will be set around locations where they are likely to smoke. An interventional message, based on mindfulness or cognitive behavior therapy, will appear if a geofence is approached. The message type will be “micro-randomized” by situation type so the researchers can learn the most effective kind of intervention for each situation.

“We’re not evaluating a particular app,” says Thrul. “We are testing fundamental principles that can inform all sorts of mobile interventions for smoking cessation.” He believes their findings could be applied to other substance addictions, too. “We’re still early in the game with these interventions, but there are some promising studies out there,” he says.