Since 1996, Congress has taken important steps to increase Medicare program integrity funding and oversight, including the establishment of the Medicare Integrity Program. Table 1 summarizes several key congressional actions. CMS has made progress in strengthening provider enrollment provisions, but needs to do more to identify and prevent potentially fraudulent providers from participating in Medicare. Additional improvements to prepayment and postpayment claims review would help prevent and recover improper payments. Addressing payment vulnerabilities already identified could further help prevent or reduce fraud. PPACA authorized and CMS has implemented new provider enrollment procedures that address past weaknesses identified by GAO and HHS's Office of Inspector General (OIG) that allowed entities intent on committing fraud to enroll in Medicare. CMS has also implemented other measures intended to improve existing procedures. Specifically, to strengthen the existing screening activities conducted by CMS contractors, the agency added screenings of categories of provider enrollment applications by risk level, contracted with new national enrollment screening and site visit contractors, and began imposing moratoria on new enrollment of certain types of providers. Screening Provider Enrollment Applications by Risk Level: CMS and OIG issued a final rule in February 2011 to implement many of the new screening procedures required by PPACA. CMS designated three levels of risk--high, moderate, and limited--with different screening procedures for categories of Medicare providers at each level. Providers in the high-risk level are subject to the most rigorous screening. Based in part on our work and that of OIG, CMS designated newly enrolling home health agencies and suppliers of durable medical equipment, prosthetics, orthotics, and supplies (DMEPOS) as high risk, and designated other providers as lower risk levels. Providers at all risk levels are screened to verify that they meet specific requirements established by Medicare, such as having current licenses or accreditation and valid Social Security numbers. High- and moderate-risk providers are also subject to unannounced site visits. Further, depending on the risks presented, PPACA authorizes CMS to require fingerprint-based criminal history checks. Last month, CMS awarded a contract that will enable the agency to access Federal Bureau of Investigation information to help conduct those checks of high-risk providers and suppliers. PPACA also authorizes the posting of surety bonds for certain providers. CMS has indicated that the agency will continue to review the criteria for its screening levels and will publish changes if the agency decides to update the assignment of screening levels for categories of Medicare providers. Doing so could become important because the Department of Justice (DOJ) and HHS reported multiple convictions, judgments, settlements, or exclusions against types of providers not currently at the high-risk level, including community mental health centers and ambulance providers. CMS's implementation of accreditation for DMEPOS suppliers, and of a competitive bidding program, including in geographic areas thought to have high fraud rates, may be helping to reduce the risk of DMEPOS fraud. While continued vigilance of DMEPOS suppliers is warranted, other types of providers may become more problematic in the future. Specifically, in September 2012, we found that a range of providers have been the subjects of fraud investigations. According to 2010 data from OIG and DOJ, over 10,000 providers that serve Medicare, Medicaid, and Children's Health Insurance Program beneficiaries were involved in fraud investigations, including not only home health agencies and DMEPOS suppliers, but also physicians, hospitals, and pharmacies.In addition, the provider type constituting the largest percentage of subjects in criminal health care fraud investigations was medical facilities--including medical centers, clinics, or practices--which constituted almost a quarter of subjects in such investigations. DMEPOS suppliers make up a little over 16 percent of subjects. National Enrollment Screening and Site Visit Contractors: CMS contracted with two new types of entities at the end of 2011 to assume centralized responsibility for two functions that had been the responsibility of multiple contractors. One of the new contractors is conducting automated screenings to check that existing and newly enrolling providers and suppliers have valid licensure, accreditation, and a National Provider Identifier (NPI), and are not on the OIG list of providers and suppliers excluded from participating in federal health care programs. The second contractor conducts site visits of providers to determine whether sites are legitimate and the providers meet certain Medicare standards. implementation of the PPACA screening requirements, the agency had revoked over 17,000 suspect providers' ability to bill the Medicare program. Site visits for DMEPOS suppliers are to continue to be conducted by the contractor responsible for their enrollment. In addition, CMS at times exercises its authority to conduct a site visit or request its contractors to conduct a site visit for any Medicare provider or supplier. Moratoria on Enrollment of New Providers and Suppliers in Certain Areas: CMS suspended enrollment of new home health providers and ambulance suppliers in certain fraud "hot spots" and other geographic areas. In July 2013, CMS first exercised its authority granted by PPACA to establish temporary moratoria on enrolling new home health agencies in Chicago and Miami, and new ambulance suppliers in Houston. In January 2014, CMS extended its first moratoria and added enrollment moratoria for new home health agency providers in Fort Lauderdale, Detroit, Dallas, and Houston, and new ground ambulance suppliers in Philadelphia. These moratoria are scheduled to be in effect until July 2014, unless CMS extends or lifts them. CMS officials cited areas of potential fraud risk, such as a disproportionate number of providers and suppliers relative to beneficiaries and extremely high utilization as rationales for suspending new enrollments of home health providers or ground ambulance suppliers in these areas. We are currently examining the ability of CMS's provider enrollment system to prevent and detect the continued enrollment of ineligible or potentially fraudulent providers in Medicare. Specifically, we are assessing the process used to enroll and verify the eligibility of Medicare providers in Medicare's Provider Enrollment, Chain, and Ownership System (PECOS) and the extent to which CMS's controls are designed to prevent and detect the continued enrollment of ineligible or potentially fraudulent providers in PECOS. Although CMS has taken many needed actions, we and OIG have found that CMS has not fully implemented other enrollment screening actions authorized by PPACA. These actions could help further reduce the enrollment of providers and suppliers intent on defrauding the Medicare program. They include issuing a rule to implement surety bonds for certain providers, issuing a rule on provider and supplier disclosure requirements, and establishing the core elements for provider and supplier compliance programs. Surety Bonds: PPACA authorized CMS to require a surety bond for certain types of at-risk providers and suppliers. Surety bonds may serve as a source for recoupment of erroneous payments. DMEPOS suppliers are currently required to post a surety bond at the time of enrollment. CMS reported in April 2014 that it had not scheduled for publication a proposed rule to implement the PPACA surety bond requirement for other types of at-risk providers and suppliers--such as home health agencies and independent diagnostic testing facilities. In light of the moratoria that CMS has placed on enrollment of home health agencies in fraud "hot spots," implementation of this rule could help the agency address potential concerns for these at-risk providers across the Medicare program. Providers and Suppliers Disclosure: CMS has not yet scheduled a proposed rule for publication for increased disclosures of prior actions taken against providers and suppliers enrolling or revalidating enrollment in Medicare, as authorized by PPACA, such as whether the provider or supplier has been subject to a payment suspension from a federal health care program. Agency officials had indicated that developing the additional disclosure requirements has been complicated by provider and supplier concerns about what types of information will be collected, what CMS will do with it, and how the privacy and security of this information will be maintained. Compliance Program: CMS has not established the core elements of compliance programs for providers and suppliers, as required by PPACA. We previously reported that agency officials indicated that they had sought public comments on the core elements, which they were considering, and were also studying criteria found in OIG model plans for possible inclusion.had not yet scheduled a proposed rule for publication. Medicare uses prepayment review to deny claims that should not be paid and postpayment review to recover improperly paid claims. As claims go through Medicare's electronic claims payment systems, they are subjected to prepayment controls called "edits," most of which are fully automated; if a claim does not meet the criteria of the edit, it is automatically denied. Other prepayment edits are manual; they flag a claim for individual review by trained staff who determine whether it should be paid. Due to the volume of claims, CMS has reported that less than 1 percent of Medicare claims are subject to manual medical record review by trained personnel. Increased use of prepayment edits could help prevent improper Medicare payments. Our prior work found that, while use of prepayment edits saved Medicare at least $1.76 billion in fiscal year 2010, the savings could have been greater had prepayment edits been used more widely. Based on an analysis of a limited number of national policies and local coverage determinations (LCD), we identified $14.7 million in payments in fiscal year 2010 that appeared to be inconsistent with four national policies and therefore improper. We also found more than $100 million in payments that were inconsistent with three selected LCDs that could have been identified using automated edits. Thus we concluded that more widespread implementation of effective automated edits developed by individual Medicare administrative contractors (MAC) in other MAC jurisdictions could also result in savings to Medicare. CMS has taken steps to improve the development of other types of prepayment edits that are implemented nationwide, as we recommended. For example, the agency has centralized the development and implementation of automated edits based on a type of national policy called national coverage determinations. CMS has also modified its processes for identifying provider billing of services that are medically unlikely to prevent circumvention of automated edits designed to identify an unusually large quantity of services provided to the same patient. We also evaluated the implementation of CMS's Fraud Prevention System (FPS), which uses predictive analytic technologies as required by the Small Business Jobs Act of 2010 to analyze Medicare fee-for-service (FFS) claims on a prepayment basis. FPS identifies investigative leads for CMS's Zone Program Integrity Contractors (ZPIC), the contractors responsible for detecting and investigating potential fraud. Implemented in July 2011, FPS is intended to help facilitate the agency's shift from focusing on recovering potentially fraudulent payments after they have been made, to detecting aberrant billing patterns as quickly as possible, with the goal of preventing these payments from being made. However, in October 2012, we found that, while FPS generated leads for investigators, it was not integrated with Medicare's payment-processing system to allow the prevention of payments until suspect claims can be determined to be valid. As of April 2014, CMS reported that while the FPS functionality to deny claims before payment had been integrated with the Medicare payment processing system in October 2013, the system did not have the ability to suspend payment until suspect claims could be investigated. In addition, while CMS directed the ZPICs to prioritize alerts generated by the system, in our work examining the sources of new ZPIC investigations in 2012, we found that FPS accounted for about 5 percent of ZPIC investigations in that year. A CMS official reported last month that ZPICs are now using FPS as a primary source of leads for fraud investigations, though the official did not provide details on how much of ZPICs' work is initiated through the system. Our prior work found that postpayment reviews are critical to identifying and recouping overpayments. The use of national recovery audit contractors (RAC) in the Medicare program is helping to identify underpayments and overpayments on a postpayment basis. CMS began the program in March 2009 for Medicare FFS. CMS reported that, as of the end of 2013, RACs collected $816 million for fiscal year 2014. PPACA required the expansion of Medicare RACs to Parts C and D. CMS has implemented a RAC for Part D, and CMS said it plans to award a contract for a Part C RAC by the end of 2014. Moreover, in February 2014, CMS announced a "pause" in the RAC program as the agency makes changes to the program and starts a new procurement process for the next round of recovery audit contracts for Medicare FFS claims. CMS said it anticipates awarding all five of these new Medicare FFS recovery audit contracts by the end of summer 2014. Other contractors help CMS investigate potentially fraudulent FFS payments, but CMS could improve its oversight of their work. CMS contracts with ZPICs in specific geographic zones covering the nation. We recently found that the ZPICs reported that their actions, such as stopping payments on suspect claims, resulted in more than $250 million in savings to Medicare in calendar year 2012. However, CMS lacks information on the timeliness of ZPICs' actions--such as the time it takes between identifying a suspect provider and taking actions to stop that provider from receiving potentially fraudulent Medicare payments--and would benefit from knowing whether ZPICs could save more money by acting more quickly. Thus, in October 2013, we recommended that CMS collect and evaluate information on the timeliness of ZPICs' investigative and administrative actions. CMS did not comment on our recommendation. We are currently examining the activities of the CMS contractors, including ZPICs, that conduct postpayment claims reviews. Our work is reviewing, among other things, whether CMS has a strategy for coordinating these contractors' postpayment claims review activities. CMS has taken steps to improve use of two CMS information technology systems that could help analysts identify fraud after claims have been paid, but further action is needed. In 2011, we found that the Integrated Data Repository (IDR)--a central data store of Medicare and other data needed to help CMS program integrity staff and contractors detect improper payments of claims--did not include all the data that were planned to be incorporated by fiscal year 2010, because of technical obstacles and delays in funding. As of March 2014, the agency had not addressed our recommendation to develop reliable schedules to incorporate all types of IDR data, which could lead to additional delays in making available all of the data that are needed to support enhanced program integrity efforts and achieve the expected financial benefits. However, One Program Integrity (One PI)--a web-based portal intended to provide CMS staff and contractors with a single source of access to data contained in IDR, as well as tools for analyzing those data--is operational and CMS has established plans and schedules for training all intended One PI users, as we also recommended in 2011. However, as of March 2014, CMS had not established deadlines for program integrity contractors to begin using One PI, as we recommended in 2011. Without these deadlines, program integrity contractors will not be required to use the system, and as a result, CMS may fall short in its efforts to ensure the widespread use and to measure the benefits of One PI for program integrity purposes. Having mechanisms in place to resolve vulnerabilities that could lead to improper payments, some of which are potentially fraudulent, is critical to effective program management, but our work has shown weaknesses in CMS's processes to address such vulnerabilities. Both we and OIG have made recommendations to CMS to improve the tracking of vulnerabilities. In our March 2010 report on the RAC demonstration program, we found that CMS had not established an adequate process during the demonstration or in planning for the national program to ensure prompt resolution of vulnerabilities that could lead to improper payments in Medicare; further, the majority of the most significant vulnerabilities identified during the demonstration were not addressed. In December 2011, OIG found that CMS had not resolved or taken significant action to resolve 48 of 62 vulnerabilities reported in 2009 by CMS contractors specifically charged with addressing fraud. We and OIG recommended that CMS have written procedures and time frames to ensure that vulnerabilities were resolved. CMS has indicated that it is now tracking vulnerabilities identified from several types of contractors through a single vulnerability tracking process, and the agency has developed some written guidance on the process. We recently examined that process and found that, while CMS informs MACs about vulnerabilities that could be addressed through prepayment edits, the agency does not systematically compile and disseminate information about effective local edits to address such vulnerabilities. Specifically, we recommended that CMS require MACs to share information about the underlying policies and savings related to their most effective edits, and CMS generally agreed to do so. In addition, in 2011, CMS began requiring MACs to report on how they had addressed certain vulnerabilities to improper payment, some of which could be addressed through edits. We also recently made recommendations to CMS to address the millions of Medicare cards that display beneficiaries' Social Security numbers, In August which increases beneficiaries' vulnerability to identity theft.2012, we recommended that CMS (1) select an approach for removing Social Security numbers from Medicare cards that best protects beneficiaries from identity theft and minimizes burdens for providers, beneficiaries, and CMS and (2) develop an accurate, well-documented cost estimate for such an option. In September 2013, we further recommended that CMS (1) initiate an information technology project for identifying, developing, and implementing changes for the removal of Social Security numbers and (2) incorporate such a project into other information technology initiatives. HHS concurred with our recommendations and agreed that removing the numbers from Medicare cards is an appropriate step toward reducing the risk of identity theft. However, the department also said that CMS could not proceed with changes without agreement from other agencies, such as the Social Security Administration, and that funding was also a consideration. Thus, CMS has not yet taken action to address these recommendations. We are currently examining other options for updating and securing Medicare cards, including the potential use of electronic-card technologies. In addition, we and others have identified concerns with CMS oversight of fraud, waste, and abuse in Medicare's prescription drug program, Part D, including the contractors tasked with this work. To help address potential vulnerabilities in that program, we are examining practices for promoting prescription drug program integrity, and the extent to which CMS's oversight of Medicare Part D reflects those practices. Although CMS has taken some important steps to identify and prevent fraud, the agency must continue to improve its efforts to reduce fraud, waste, and abuse in the Medicare program. Identifying the nature, extent, and underlying causes of improper payments, and developing adequate corrective action processes to address vulnerabilities, are essential prerequisites to reducing them. As CMS continues its implementation of PPACA and Small Business Jobs Act provisions, additional evaluation and oversight will help determine whether implementation of these provisions has been effective in reducing improper payments. We are investing resources in a body of work that assesses CMS's efforts to refine and improve its fraud detection and prevention abilities. Notably, we are currently assessing the potential use of electronic-card technologies, which can help reduce Medicare fraud. We are also examining the extent to which CMS's information system can help prevent and detect the continued enrollment of ineligible or potentially fraudulent providers in Medicare. Additionally, we have a study underway examining CMS's oversight of fraud, waste, and abuse in Medicare Part D to determine whether the agency has adopted certain practices for ensuring the integrity of that program. We are also examining CMS's oversight of some of the contractors that conduct reviews of claims after payment. These studies are focused on additional actions for CMS that could help the agency more systematically reduce potential fraud in the Medicare program. Chairman Brady, Ranking Member McDermott, and Members of the Subcommittee, this concludes my prepared remarks. I would be pleased to respond to any questions you may have at this time. For further information about this statement, please contact Kathleen M. King at (202) 512-7114 or kingk@gao.gov. Contact points for our Offices of Congressional Relations and Public Affairs may be found on the last page of this statement. Karen Doran, Assistant Director; Stephen Robblee; Lisa Rogers; Eden Savino; and Jennifer Whitworth were key contributors to this statement. Medicare: Second Year Update for CMS's Durable Medical Equipment Competitive Bidding Program Round 1 Rebid. GAO-14-156. Washington, D.C.: March 7, 2014. Medicare Program Integrity: Contractors Reported Generating Savings, but CMS Could Improve Its Oversight. GAO-14-111. Washington, D.C.: October 25, 2013. Medicare Information Technology: Centers for Medicare and Medicaid Services Needs to Pursue a Solution for Removing Social Security Numbers from Cards. GAO-13-761. Washington, D.C.: September 10, 2013 Health Care Fraud and Abuse Control Program: Indicators Provide Information on Program Accomplishments, but Assessing Program Effectiveness Is Difficult. GAO-13-746. Washington, D.C.: September 30, 2013. Medicare Program Integrity: Increasing Consistency of Contractor Requirements May Improve Administrative Efficiency. GAO-13-522. Washington, D.C.: July 23, 2013. Medicare Program Integrity: Few Payments in 2011 Exceeded Limits under One Kind of Prepayment Control, but Reassessing Limits Could Be Helpful. GAO-13-430. Washington, D.C.: May 9, 2013. 2013 Annual Report: Actions Needed to Reduce Fragmentation, Overlap, and Duplication and Achieve Other Financial Benefits. GAO-13-279SP. Washington, D.C.: April 9, 2013. Medicare Fraud Prevention: CMS Has Implemented a Predictive Analytics System, but Needs to Define Measures to Determine Its Effectiveness. GAO-13-104. Washington, D.C.: October 15, 2012. Medicare Program Integrity: Greater Prepayment Control Efforts Could Increase Savings and Better Ensure Proper Payment. GAO-13-102. Washington, D.C.: November 13, 2012. Medicare: CMS Needs an Approach and a Reliable Cost Estimate for Removing Social Security Numbers from Medicare Cards. GAO-12-831. Washington, D.C.: August 1, 2012. Health Care Fraud: Types of Providers Involved in Medicare, Medicaid, and the Children's Health Insurance Program Cases. GAO-12-820. Washington, D.C.: September 7, 2012. Program Integrity: Further Action Needed to Address Vulnerabilities in Medicaid and Medicare Programs. GAO-12-803T. Washington, D.C.: June 7, 2012. Follow-up on 2011 Report: Status of Actions Taken to Reduce Duplication, Overlap, and Fragmentation, Save Tax Dollars, and Enhance Revenue. GAO-12-453SP. Washington, D.C.: February 28, 2012. Medicare: The First Year of the Durable Medical Equipment Competitive Bidding Program Round 1 Rebid. GAO-12-733T. Washington, D.C.: May 9, 2012. Medicare: Review of the First Year of CMS's Durable Medical Equipment Competitive Bidding Program's Round 1 Rebid. GAO-12-693. Washington, D.C.: May 9, 2012. Medicare: Important Steps Have Been Taken, but More Could Be Done to Deter Fraud. GAO-12-671T. Washington, D.C.: April 24, 2012. Medicare Program Integrity: CMS Continues Efforts to Strengthen the Screening of Providers and Suppliers. GAO-12-351. Washington, D.C.: April 10, 2012. Improper Payments: Remaining Challenges and Strategies for Governmentwide Reduction Efforts. GAO-12-573T. Washington, D.C.: March 28, 2012. 2012 Annual Report: Opportunities to Reduce Duplication, Overlap and Fragmentation, Achieve Savings, and Enhance Revenue. GAO-12-342SP. Washington, D.C.: February 28, 2012. Fraud Detection Systems: Centers for Medicare and Medicaid Services Needs to Expand Efforts to Support Program Integrity Initiatives. GAO-12-292T. Washington, D.C.: December 7, 2011. Medicare Part D: Instances of Questionable Access to Prescription Drugs. GAO-12-104T. Washington, D.C.: October 4, 2011. Medicare Part D: Instances of Questionable Access to Prescription Drugs. GAO-11-699. Washington, D.C.: September 6, 2011. Medicare Integrity Program: CMS Used Increased Funding for New Activities but Could Improve Measurement of Program Effectiveness. GAO-11-592. Washington, D.C.: July 29, 2011. Improper Payments: Reported Medicare Estimates and Key Remediation Strategies. GAO-11-842T. Washington, D.C.: July 28, 2011. Fraud Detection Systems: Additional Actions Needed to Support Program Integrity Efforts at Centers for Medicare and Medicaid Services. GAO-11-822T. Washington, D.C.: July 12, 2011. Fraud Detection Systems: Centers for Medicare and Medicaid Services Needs to Ensure More Widespread Use. GAO-11-475. Washington, D.C.: June 30, 2011. Improper Payments: Recent Efforts to Address Improper Payments and Remaining Challenges. GAO-11-575T. Washington, D.C.: April 15, 2011. Medicare and Medicaid Fraud, Waste, and Abuse: Effective Implementation of Recent Laws and Agency Actions Could Help Reduce Improper Payments. GAO-11-409T. Washington, D.C.: March 9, 2011. Opportunities to Reduce Potential Duplication in Government Programs, Save Tax Dollars, and Enhance Revenue. GAO-11-318SP. Washington, D.C.: March 1, 2011. Improper Payments: Progress Made but Challenges Remain in Estimating and Reducing Improper Payments. GAO-09-628T. Washington, D.C.: April 22, 2009. Medicare: Thousands of Medicare Providers Abuse the Federal Tax System. GAO-08-618. Washington, D.C.: June 13, 2008. Medicare: Competitive Bidding for Medical Equipment and Supplies Could Reduce Program Payments, but Adequate Oversight Is Critical. GAO-08-767T. Washington, D.C.: May 6, 2008. Improper Payments: Status of Agencies' Efforts to Address Improper Payment and Recovery Auditing Requirements. GAO-08-438T. Washington, D.C.: January 31, 2008. Improper Payments: Federal Executive Branch Agencies' Fiscal Year 2007 Improper Payment Estimate Reporting. GAO-08-377R. Washington, D.C.: January 23, 2008. Medicare: Improvements Needed to Address Improper Payments for Medical Equipment and Supplies. GAO-07-59. Washington, D.C.: January 31, 2007. Medicare: More Effective Screening and Stronger Enrollment Standards Needed for Medical Equipment Suppliers. GAO-05-656. Washington, D.C.: September 22, 2005. Medicare: CMS's Program Safeguards Did Not Deter Growth in Spending for Power Wheelchairs. GAO-05-43. Washington, D.C.: November 17, 2004. Medicare: CMS Did Not Control Rising Power Wheelchair Spending. GAO-04-716T. Washington, D.C.: April 28, 2004. This is a work of the U.S. government and is not subject to copyright protection in the United States. The published product may be reproduced and distributed in its entirety without further permission from GAO. However, because this work may contain copyrighted images or other material, permission from the copyright holder may be necessary if you wish to reproduce this material separately.

Summary:
GAO has designated Medicare as a high-risk program, in part because the program's size and complexity make it vulnerable to fraud, waste, and abuse. In 2013, Medicare financed health care services for approximately 51 million individuals at a cost of about $604 billion. The deceptive nature of fraud makes its extent in the Medicare program difficult to measure in a reliable way, but it is clear that fraud contributes to Medicare's fiscal problems. More broadly, in fiscal year 2013, CMS estimated that improper payments--some of which may be fraudulent--were almost $50 billion. This statement focuses on the progress made and important steps to be taken by CMS and its program integrity contractors to reduce fraud in Medicare. These contractors perform functions such as screening and enrolling providers, detecting and investigating potential fraud, and identifying improper payments and vulnerabilities that could lead to payment errors. This statement is based on relevant GAO products and recommendations issued from 2004 through 2014 using a variety of methodologies. In April 2014, GAO also received updated information from CMS on its actions related to the laws, regulations, and guidance discussed in this statement. Additionally, GAO updated information by examining public documents and relevant policies and procedures. The Centers for Medicare & Medicaid Services (CMS)--the agency within the Department of Health and Human Services (HHS) that oversees Medicare--has made progress in implementing several key strategies GAO identified in prior work as helpful in protecting Medicare from fraud; however, important actions that could help CMS and its program integrity contractors combat fraud remain incomplete. Provider Enrollment : The Patient Protection and Affordable Care Act (PPACA) authorized, and CMS has implemented, actions to strengthen provider enrollment that address past weaknesses identified by GAO and HHS's Office of Inspector General. For example, CMS has hired contractors to determine whether providers and suppliers have valid licenses and are at legitimate locations. CMS also recently contracted for fingerprint-based criminal history checks for high-risk providers and suppliers. CMS could further strengthen provider enrollment by issuing a rule to require additional provider and supplier disclosures of information and establishing core elements for provider and supplier compliance programs, as authorized by PPACA. Prepayment and Postpayment Claims Review : Medicare uses prepayment review to deny claims that should not be paid and postpayment review to recover improperly paid claims. GAO has found that increased use of prepayment edits could help prevent improper Medicare payments. For example, prior GAO work identified millions of dollars of payments inconsistent with selected coverage and payment policies and therefore improper. Postpayment reviews are also critical to identifying and recouping payments. GAO recommended better oversight of both the information systems analysts use to identify claims for postpayment review, in a 2011 report, and the contractors responsible for these reviews, in a 2013 report. CMS has addressed some of these recommendations. Addressing Identified Vulnerabilities : Having mechanisms in place to resolve vulnerabilities that could lead to improper payments is critical to effective program management and could help address fraud. However, GAO work has shown weaknesses in CMS's processes to address such vulnerabilities, placing the Medicare program and its beneficiaries at risk. For example, GAO has made multiple recommendations to CMS to remove Social Security numbers from beneficiaries' Medicare cards to help prevent identity theft, and, while HHS agreed with these recommendations, the department also reported that CMS could not proceed with the changes for a variety of reasons, including funding limitations. Thus, to date, CMS has not taken action on these recommendations. GAO has work underway addressing these key strategies, including assessing the potential use of electronic-card technologies to help reduce Medicare fraud. GAO is also examining the extent to which CMS's information system can prevent and detect the continued enrollment of ineligible or potentially fraudulent providers in Medicare. Additionally, GAO is studying CMS's oversight of program integrity efforts for prescription drugs and is examining CMS's oversight of some of the contractors that conduct reviews of claims after payment. These studies are focused on additional actions for CMS that could help the agency more systematically reduce potential fraud in the Medicare program.