Up front about low back imaging: MRI rates consistent despite CMS initiative

A recent public reporting initiative from the Centers for Medicare & Medicaid Services (CMS) has had little to no effect on MRI examination rates for low back pain prior to conservative therapy, according to results of a study published online Mar. 9 in Radiology.

As one of the most notorious sources of likely excessive scans, imaging for low back pain is estimated to be responsible for as much as $300 million in wasteful medical spending annually. For this reason, initiatives including Choosing Wisely and others explicitly target low back imaging as part of their efforts to reduce costs and unnecessary patient exposure to radiation and contrast agents. In particular, the CMS initiative is part of the incentive-based Hospital Outpatient Quality Reporting (OQR) Imaging Efficiency Measures, which address specific scenarios in which imaging procedures are often overused and use reporting data to determine facility reimbursement.

Researchers Cecilia Ganduglia, MD, of the University of Texas School of Public Health, and colleagues set out to determine what effect, if any, the CMS public reporting initiative is having on low back MRI examination rates. The team performed a retrospective analysis of Medicare fee-for-service claims as well as those made to the private insurer Blue Cross Blue Shield of Texas (BCBSTX) by Texas residents from 2008 through 2011. Data was analyzed using the OQR’s imaging efficiency measure OP-8, which calculates the percentage of MRI examinations ordered without prior conservative therapy compared with all MRI scans ordered for patients presenting with low back pain. Endpoints of the study included OP-8 rates, trends and regional variation.

Their results revealed that despite the CMS initiative, there has been no significant reduction in low back MRI examinations during the study’s timeframe. “It does not appear as if the public reporting program has helped reduce the percentage of MR imaging examinations for low back pain that are potentially unnecessary,” wrote Ganduglia, et al. “The Medicare OP-8 state mean for OHD settings remained essentially unchanged from 2008 through 2011, and, if anything, increased slightly at the hospital referral region level. A similar pattern was found … for the comparable BCBSTX settings.”

Despite study limitations such as lack of control group, regional bias and some uncertainty among health professionals about what exactly constitutes an efficient OP-8 rate, the researchers believe their findings are evidence that reduction of excessive imaging is not easily achieved by universal public reporting requirements. “The lack of a significant reduction in the use of MR imaging for low back pain without history of conservative therapy suggests that simply requiring hospitals to report such rates is not sufficient to reduce imaging practices,” the authors concluded.