Technology is just one health tool, reminds the New York Times.

While the proliferation of fitness trackers suggests there is commercial potential in consumer health data technology, utility may be limited. “I don’t doubt the wearable piece is going to be a productive business model for people,” Ian T. Clark, chief executive of Genentech, said at the conference. “I just don’t know whether it’s going to bend the curve in health outcomes.”

Last month Aetna announced it was discontinuing CarePass, its personalized health data platform for patients, because it hadn’t delivered on anticipated results. And some studies show that half the people who buy portable fitness trackers stop using them in a matter of months. That is probably because most people who wear them are already health-conscious and there may be little long-term value once they take note of their activity patterns, Mr. Van Kuiken suggested.