New technology uses standard features on smartphones – GPS and movement tracking – to monitor a patient’s behavior and alert the doctor when something seems out of order.

A handful of hospitals and medical centers have recently begun testing and using the technology, with financial backing for these digital flares coming from medical chains, the United States military and insurance companies.

The novel approach relies on technology that is increasingly standard on smartphones: global positioning systems and accelerometers that can track location and movement.

“It’s a potential human early-warning system, the body’s check-engine light,” said Michael Seid, a professor of pediatrics at Cincinnati Children’s Hospital Medical Center. Since last year, 15 patients with chronic gastrointestinal trouble have carried the phones to test the software’s effectiveness. The results so far indicate that some patients clearly change their communication and movement patterns in the days before the onset of severe symptoms.

“When your pain increases, you’re less likely to be at the park or the mall. It could be early indicators of a flare-up or worsening of the disease,” Dr. Seid said. The technology, he added, “measures social behavior at a scale and depth you just didn’t have before.”

The software is still being tested and studied for its effectiveness. But mental health experts and researchers say it shows great promise — not just for spotting worsening conditions, but also for picking up on behavior changes that suggest someone has stopped taking medication or needs a dosage change….

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