SAN FRANCISCO—Jody Kearns doesn’t like to spend time obsessing about her Parkinson’s disease. The 56-year-old dietitian from Syracuse, New York, had to give up bicycling because the disorder affected her balance. But she still works, drives and tries to live a normal life.
Yet since she enrolled in a clinical study that uses her iPhone to gather information about her condition, Kearns has been diligently taking a series of tests three times a day. She taps the phone’s screen in a certain pattern, records a spoken phrase and walks a short distance while the phone’s motion sensors measure her gait.
