WEDNESDAY, Nov. 30, 2011 (HealthDay News) -- Patients are much more likely to undergo unnecessary medical imaging exams if the tests are ordered by doctors with a financial interest in the imaging equipment, according to a new study.
In order to scrutinize this self-referred imaging, researchers examined 500 diagnostic lumbar spine MRIs ordered by two orthopedic physician groups in the same community. One group had a financial interest in the MRI equipment while the second group had no financial interest in the equipment.
There were no significant differences between the two groups in terms of the number of abnormalities per positive scan, but the mean age among patients in the financial-interest group was significantly younger -- a mean of 50 years, compared with 56 for those in the no-financial-interest group.
There were 86 percent more negative scans in the financial interest group (106 of 250 or 42 percent) than in the no-financial-interest group (57 of 250 or 23 percent), which indicates a much higher number of potentially unnecessary MRIs, according to the researchers.
The study was to be presented Wednesday at the annual meeting of the Radiological Society of North America in Chicago.
"Orthopedic surgeons with financial interest in the equipment had a much higher rate of negative lumbar spine MRIs," Dr. Ben Paxton, a radiology resident at Duke University Medical Center, said in an RSNA news release. "In addition, they were much more likely to order MRI exams on younger patients. This suggests that there is a different clinical threshold for ordering MRI exams in the setting of financial incentivization."
The increasing use of medical imaging through doctors' self-referral may not provide any medically useful information and may actually place patients at potential risk and contribute to escalating medical costs, Paxton noted.
"It is important for patients to be aware of the problem of self-referral and to understand the conflict of interest that exists when their doctor orders an imaging exam and then collects money on that imaging exam," he said.
Because this study was presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
The U.S. Food and Drug Administration has more about medical imaging.