Insurers, hospitals and other healthcare providers say they are purchasing consumer data to help patients live a healthier lifestyle. But privacy advocates think it's slippery slope.

Blue Cross Blue Shield of North Carolina says it buys consumer data in order to identify members who might benefit from extra tools or treatments for various health issues, like obesity or diabetes.

Meanwhile, Carolinas HealthCare System, a network of hospitals, medical centers and doctors offices in North and South Carolina, is experimenting with combining consumer data with medical records to predict things like a patient's risk of having a heart attack.

"We can provide benefits to our patients with the same mechanism that are used to sell people more stuff," said Dr. Michael Dulin, the system's chief clinical officer for analytics and outcomes research.

Citing the company's contract with its data broker, Dulin wouldn't disclose the exact kinds of data being used. But he said the information will not be shared with other parties.

While federal law dictates that a person's information can't be used to outright deny them insurance coverage, privacy advocates say there are other issues at stake.

Consumer data collected by data brokers can be "startling inaccurate," for example, said World Privacy Forum Executive Director Pam Dixon. "Are hospitals using inaccurate data to do [this] analysis?" she asked.

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