Google Health users enter information — such as medications taken, procedures undergone, allergies and lab tests — and merge what previously had been separate pieces of information into a single easily accessed record.

You had a mole removed last year. Maybe that was the year before? Then your primary-care doctor put you on a medication to lower cholesterol. Or was that a blood-thinner? And which antibiotic are you allergic to?

Google Health is intended to clear up that confusion. The medical records service, launched by the popular search engine Google in May 2008, lets users enter information, such as medications taken, procedures undergone, allergies and lab tests, merging what previously had been separate pieces of information into a single easily accessed record.

Such centralization of information is supposed to eliminate redundant paperwork and testing, keep track of diagnoses and medication and reduce costs. It also allows the creation of one place where patients can keep their medical records from all sources — physicians, clinics, hospitals, labs and radiology.

Patients can enter the information manually, or if their hospital or pharmacy is partnered with Google Heath, copies of their medical records or prescriptions can be sent right to their profile. Health organizations and pharmacies such as Beth Israel Deaconess Medical Centre, Blue Cross Blue Shield of Massachusetts, Cleveland Clinic and CVS can connect with Google Health. Other health-care partners likely will be added soon.

Google Health can access only medical information volunteered by individuals. It does not retrieve any records unless patients explicitly direct it to. The service is free and, unlike its Microsoft counterpart, HealthVault, it does not run advertising. The service also enables patients to search for physicians and hospitals, find information on specific diseases and learn how medications interact.

Benefits outweigh the risks

Although acknowledging that such a public transfer of data has its dangers, James Gibney in The Atlantic wrote that the benefits outweigh the risks. He noted that easy access to personal health records could prevent medical errors such as incorrectly prescribed medications and erroneous diagnoses, while reducing costs by eliminating unnecessary tests, procedures and paperwork.

Gibney said hacking into patient records is less likely to endanger patient privacy than is institutional carelessness, while government health-care organizations are not good with privacy anyway. Since Google is not a health-care provider, it is not covered by the Health Insurance Portability and Accountability Act.

"Google is arguably better equipped to prevent such lapses," Gibney wrote, "and more fundamentally interested in doing so, since breaches would undermine public confidence in the company and might expose it to greater regulation."

However, to complicate matters, in an article in the New England Journal of Medicine, two leading researchers warned that the entry of companies such as Microsoft and Google into the field of personal health records could drastically alter the practice of clinical research and raise new challenges to the privacy of patient records.

The authors, Dr Kenneth D. Mandl and Dr Isaac S. Kohane, have long advocated the use of electronic records to improve medical care and decision-making by patients. However, they are concerned that the medical profession and lawmakers do not understand the vast implications of companies such as Microsoft and Google becoming the hosts for huge stores of patient information. Consumer control of personal data under these new, unregulated online systems could open the door to massive marketing and false advertising.

These physicians said they are enthusiastic about the potential benefits of Web-based personal health records, including patients who are better informed and more responsible for their health.

"In very short order, a few large companies could hold larger patient databases than any clinical research centre anywhere," Dr Mandl told The New York Times.

Those data may soon be growing even more. Google, along with IBM and the Continua Health Alliance, recently unveiled software that allows personal medical devices, such as blood-sugar monitors, to send information straight to the patients' Google Health accounts. (Continua Health Alliance is an organization that promotes interoperability of medical devices.)

A careful reading of Google Health's terms of service shows that privacy is still an issue. What if Google is sold? Can the government order release of a Google Health record? Can a potential employer buy and see health records? Some of the questions do not have clear answers.

Meanwhile, for America's economic recovery package, the Obama administration plans to spend $19 billion to accelerate the use of computerized medical records in physicians' offices. Expect to see greater pressure for it in your practice soon, if you haven't already.