Research continues to suggest that self-referred imaging exams often are unnecessary.
In a new study, published online Sept. 17 in Radiology, researchers, led by Matthew Lungren, M.D., of Duke Medical Center, analyzed how owning MRI equipment would impact the likelihood of positive or negative findings while imaging knees.
The researchers reviewed 700 consecutive diagnostic MRI exams from 667 patients. The exams were interpreted by a radiology practice between January and April 2009, and were referred by two different orthopedic physicians groups; one of the groups had a financial interest in the MRI equipment used, while the other did not. The 700 MRI exams were split evenly between the two groups.
According to the authors, knee MRIs ordered by the physician's group with a financial interest in the MRI unit used were 33 percent more likely to be negative than those MRIs ordered by the group with no financial interest. There were a total of 205 negative exams, 117 of which came from the physician's group with the financial interest in the MRI equipment.
"This [the differences in the number of negative exams ordered] occurred despite otherwise highly similar pathology, demographics and referring physician characteristics between the two groups," Lungren said in an announcement. "These findings suggest that there is a different threshold for ordering MRI examinations, which may be due to financial incentive."
This is just the latest study making the connection between self-referrals and negative testing. As previously reported in FierceMedicalImaging, a study in the September issue of the American Journal of Roentgenology found that physician groups that own their own MRI scanners ordered more shoulder scans that turned out to be negative--by a difference of 25.6 percent--than groups with no financial interest in the equipment used.