Twenty providers of portable X-ray services have exhibited "questionable" billing practices, inspectors with the Department of Health and Human Services said in a new report that calls on the Centers for Medicare and Medicaid Services to put the industry under closer scrutiny.

In the report, released Wednesday, the Office of the Inspector General also said providers have collected millions of dollars in apparent overpayments, which the CMS should take back, as the agency works on a plan to prevent similar mishaps in the future. The OIG said the CMS agrees with its recommendations.

"Portable x-rays constitute a small portion of overall Medicare payments for diagnostic imaging services, but the questionable claims patterns we found raise concerns about the integrity of payments to certain suppliers," the office, under Inspector General Daniel R. Levinson, noted in its report.

Portable X-ray suppliers visit non-clinical settings such as nursing homes and group-living places and take X-rays of patients who can't make it to the hospital. Medicare generally pays for the transport of the equipment, as well as costs involved in taking the scan and interpreting the images. CMS paid about $225 million for these services in 2009, the OIG said.

But the inspectors said some of the payments should be re-collected. For instance, in 2009, Medicare paid about $6.6 million for tests ordered by non-physicians, mostly nurse-practitioners, although CMS only reimburses for exams requested by licensed doctors.

Also in 2009, Medicare spent another $12.8 million to cover transport costs for multiple trips to the same institution on the same day. While this is covered by Medicare, OIG suspects some providers incorrectly billed for multiple trips when all patients were seen in a single visit.

"As a typical example, one supplier submitted two separate claims for transportation costs, one for each of two beneficiaries, on a particular day, " the OIG report read. "However...these two beneficiaries were located in the same nursing home on that date. Claims data do not provide sufficient information to determine whether the supplier billed correctly for two separate trips to the facility or administered tests to the two beneficiaries during a single trip and failed to use the appropriate prorated billing code."

"Questionable" practices

In its review of portable X-ray suppliers, the OIG developed a formula to help identify suspicious billing patterns. This included looking for suppliers who had a lot of tests ordered by non-doctors, or for exams where the patient hadn't seen the ordering provider for a long time -- that is, for more than six weeks.

Of the 352 suppliers examined, about 20 aroused OIG's suspicions. Unsurprisingly, perhaps, over half of the questionable suppliers were located in and around Miami, an area known for its Medicare shenanigans. To give an example of the kind of behavior that stood out, the OIG said for the most suspicious supplier, services ordered by non-doctors accounted for almost one-third of its charges. For other providers, this only accounted for a median 1 percent, the OIG said.

Recommendations

OIG's five recommendations to CMS are (from the OIG's release):

1) Take appropriate action on portable x-ray suppliers referred by OIG,

(2) Establish a process to periodically identify portable x-ray suppliers that merit greater scrutiny and follow up as appropriate,

(3) Determine what portion of the $12.8 million it paid for return trips in 2009 actually reimbursed suppliers for incorrectly billed transportation component claims and collect any overpayments,

(4) Collect the $6.6 million in overpayments it made for portable x-ray services rendered in 2009 that were ordered by non-physicians, and

(5) Implement procedures to ensure that it pays for portable x-ray services only when they are ordered by a physician and establish appropriate controls.