Physicians who own or lease MRI equipment are more likely than those who do not have such equipment in-house to perform scans on patients with low back pain, according to a study performed at Stanford University. Results of the study, published online yesterday in Health Services Research, also indicated that patients whose orthopedists perform MRI studies on them for low back pain are more likely to subsequently undergo back surgery.
In conducting the study, Stanford University researchers reviewed scan rates for Medicare patients of 1,033 primary care physicians and 1,271 orthopedists before and after practitioners had acquired MRI equipment. The scope of the research involved MRI scanners that had been purchased directly from manufacturers, as well as those installed under terms of lease arrangements wherein physicians would be billed directly for any scans they had ordered. Lead researcher Jacqueline Baras Shreibati, MD, and her colleagues discovered that the rate of MRI scans increased by 13% for orthopedists' patients and by 32% for patients of primary care doctors, a trend they attributed to attributed to increases to financial incentives that seemed to influence physicians' behavior and decisions.
The researchers’ analysis also revealed that patients who visited an orthopedist after an MRI scan were 34% more likely to undergo back surgery within six months. There was no definitive evidence that either the MRI or surgery for low back pain improved patients' outcomes.
Shreibati and her collegues note that while their intent was not to determine whether the additional surgeries were necessary, the results clearly demonstrate direct relationship between imaging and surgery in a group of patients for whom surgery can be a controversial treatment option. Federal regulations prohibit physicians from referring Medicaid or Medicare patients for health services in which they have a financial interest. However, an exception exists for in-office procedures, including MRI scans done with offsite equipment leased on a per-scan basis.