The OIG and the Government Accountability Office (GAO) have issued several reports regarding the Medicare Part D drug program. In a report entitled “Medicare Drug Plan Sponsors' Identification of Potential Fraud and Abuse,” the OIG recommends a number of steps to address fraud and abuse. For instance, the OIG calls on CMS to: review variances in potential fraud and abuse among plans; determine if Part D prescription drug plan (PDP) sponsors investigated and corrected potential abuses; and require PDP sponsors to report on their fraud and abuse programs. In a separate report, “Oversight of Prescription Drug Plan Sponsors' Compliance Plans,” the OIG found that CMS conducted only one focused audit and no routine audits of PDP sponsors’ compliance plans in 2007. Further, CMS did not verify sponsor’s responses to a compliance plan self-assessment. CMS agreed with an OIG recommendation that CMS conduct audits to verify that PDP sponsors' compliance plans meet regulatory and manual requirements. Additionally, an OIG report on "Centers for Medicare & Medicaid Services Audits of Medicare Part D Bids" found that one-quarter of all bid audits completed for plan years 2006 and 2007 identified at least one material finding, but CMS has not adjusted PDP sponsors’ bid amounts based on such findings. The OIG recommends that CMS hold plan sponsors more accountable for material findings identified in bid audits, and conduct the required number of financial audits in a timely manner. Finally, the GAO has reported on "Medicare Part D Prescription Drug Coverage: Federal Oversight of Reported Price Concessions Data." The GAO found that CMS has initiated about half of its planned detailed financial audits to examine Part D price concessions data for 2006, with the rest delayed due to financial constraints. The audits are expected to be completed by October 2009. CMS also pointed to variation in defining and reporting price concessions data, such as differences in how sponsors allocate manufacturer rebates between their Part D plans and other business, as likely creating oversight challenges.