Doctors and patients have turned a watchful eye toward radiation dosage in recent years. But doing so can be dicey without a complete picture of what tests hospitals are administering over the course of time.

Intermountain Healthcare, Salt Lake City, is attempting to sort it out by tracking each patient's cumulative radiation exposure throughout its 22 hospitals and 185 clinics. Officials at the health system believe it's the first to offer such a service, allowing consumers to view their entire radiation history through electronic health records. Intermountain leaders hope the record will discourage doctors from requesting unnecessary imaging tests and patients from opting out of exams for fear of harm.

"It's a growing concern nationally and it's a growing concern for individual patients," says Keith White, M.D., medical director of imaging services at Intermountain. "Our intent is to try to take a very complicated topic and, in a balanced and objective way, provide information to people that they could really use to make good decisions."

The Joint Commission estimates that Americans' exposure to ionizing radiation has almost doubled in the past 20 years, with physicians sometimes ordering tests oblivious to the patient's history. The higher the dose of radiation delivered in one test, or in multiple doses over time, the higher the risk of harm, according to a 2011 Joint Commission Sentinel Event Alert.

Intermountain is tracking the history of all patients receiving four of the highest-dose procedures, starting with exams performed in the last quarter of 2012. The health system also offers educational materials to explain the risks and rewards of radiation exposure.

Just by closely tracking data and starting a conversation about the numbers, Intermountain has reduced the average dose for cath lab studies by 15 to 20 percent, says Donald Lappé, M.D., medical director of the cardiovascular clinical program.

"People who are intended to provide the best care for their patients will take it on themselves to develop strategies and to apply standards that will reduce radiation," he says. "It's actually been very exciting to see this halo benefit to the community that we serve."

White stresses that what Intermountain is trying is "very imperfect" at this early stage. Procedures before late 2012 aren't included in the record, and physicians are unable to track tests performed outside the system. The eventual creation of a national radiation dosage registry as part of a health information exchange will help to further clear the picture, he adds.

Compiling the information is one thing, but are patients actually curious to see it? One GE Healthcare survey found that only about 15 percent of the population is aware of the risks of medical radiation, says Ken Denison, CT dose leader at GE. He expects that number to grow, though, as consumers become savvier about their health.

"Like everything I've seen in health care in my almost 30 years on this side of the industry, nothing will happen quickly, but momentum will build," Denison says. "Consumers are clearly getting more informed, so I expect there to be more conversations, and health care systems like Intermountain are starting to recognize and get ready to have those conversations."