A new federal proposal to give all patients in the U.S. direct electronic access to their lab results could make it easier to track important health markers like cholesterol levels and the body's response to blood thinners ? ? with an iPhone. The rules proposed by the Dept. of Health and Human Services are part of a broader effort to give patients more access to their own medical data, so they can become more engaged in their care. They would replace a confusing patchwork of state laws and privacy statutes and affect more than six billion lab tests a year. Under current law, a lab may only release tests results directly to patients if a health-care provider authorizes it at the time of the test or if patients live in one of seven states, Puerto Rico or the District of Columbia, which expressly allow direct release to patients. Quest Diagnostics, the big lab company that provides testing services to about half of doctors and hospitals, already fulfills about a million requests for direct patient data a year, mostly via fax, but says a growing number are getting direct access through Gazelle, a free mobile app it launched last October. The company says adoption has accelerated in recent months and is now approaching 100,000 users.