A primary benefit, Schmidt said, is the portability of records from one healthcare provider to the next. He repeatedly said no data would be shared without the consumer's consent.
"Our model is that the owner of the data has control over who can see it," Schmidt said at the annual conference of the Healthcare Information and Management Systems Society. "And trust, for Google, is the most important currency on the Internet."
The service is not yet available publicly, but Schmidt said it will be an open system where third parties can build direct-to-consumer services like medication tables or immunization reminders. Google intends to profit by increasing traffic to its search site - the same approach it used with the ad-free Google News section.
The Mountain View, Calif., company isn't the only one vying for the personal health record market. Microsoft Corp. last year introduced a service called HealthVault, and AOL cofounder Steve Case is backing Revolution Health, which offers similar online tools.
Microsoft's service has ads, but they aren't personalized based on health records or searches. Revolution Health does not have ads on its health records service.
Google has raised privacy concerns in other areas by tailoring ads based on search requests, and its e-mail service scans the text of messages to flash pitches from businesses that seem to offer corresponding products or services.
The bigger problem with these online health systems, privacy advocates say, is that they aren't covered by the federal Health Insurance Portability and Accountability Act, commonly called HIPAA. The 1996 privacy law requires patient notification when their records are being subpoenaed, among other things.
"Once you take sensitive healthcare information outside of the healthcare sector, it loses important protections that people have come to expect," said Pam Dixon, executive director of the nonprofit World Privacy Forum. "Your physician has taken a Hippocratic Oath, and they are bound to have your best interests in mind. A publicly traded company is supposed to have shareholders in mind first." Dixon said even the issue of consenting online to the release of information is muddy.
Schmidt said Google Health would be at least as secure as current systems.
Schmidt described the service as helping both doctors and the increasing number of patients who use the Internet for their own medical research.
Google Health partners include retailers with pharmacies like Wal-Mart Stores Inc., and healthcare providers such as Aetna Inc. and Cedars-Sinai Medical Center.
