A report issued Monday by the Government Accountability Office says the Centers for Medicare & Medicaid Services should extend tests of a prior authorization program that have saved up to $1.9 billion.

In an effort to reduce improper payments and reduce expenses, the Medicare program  launched a seven-state pre-authorization pilot in 2012 for certain power mobility devices, including power wheelchairs.

Medicare Administrative Contractors review beneficiary requests and make determinations to approve or deny them based on Medicare coverage and payment rules. The program was set to expire in 2018, but the GAO recommends adding essential power wheelchair accessories to the demonstration and continuing the whole thing.

“Providers and suppliers reported benefits from the approach, but also had concerns about uncertainties created over what is covered,” the report states. “Challenges … include difficulty obtaining the necessary documentation from referring physicians to submit a prior authorization request, although CMS has created templates and other tools to address this concern. In addition, providers and suppliers reported concerns about whether accessories deemed essential to the power wheelchairs under the permanent durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) program are subject to prior authorization.”

In its response, the Department of Health and Human Services said it would consider the recommendations, including whether to extend the timeline past this August, restart a paused home health demonstration or identify new opportunities for additional items with“high unnecessary utilization.”