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Medicare Advantage: Actions Needed to Enhance CMS Oversight of Provider Network Adequacy

GAO-15-710 Published: Aug 31, 2015. Publicly Released: Sep 28, 2015.
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What GAO Found

The Centers for Medicare & Medicaid Services (CMS) is the agency within the Department of Health and Human Services (HHS) responsible for overseeing the Medicare Advantage (MA) program—Medicare's private plan alternative. Since 2011, CMS has defined an adequate MA provider network as meeting two criteria: a minimum number of providers and maximum travel time and distance to those providers. To reflect local conditions, the requirements are specific to different county types and a range of provider types. However, the MA criteria do not reflect aspects of provider availability, such as how often a provider practices at a given location. In contrast, other network-based health programs use provider availability measures to assess network adequacy. For example, federal Medicaid managed care rules address providers' ability to accept new patients and TRICARE criteria address appointment wait times for active duty servicemembers. Without taking availability into account, as is done in some other programs, MA provider networks may appear to CMS and beneficiaries as more robust than they actually are.

CMS applies its network adequacy criteria narrowly. Rather than assessing all county-based provider networks against its criteria, CMS limits its annual application of the criteria to provider networks in counties that MA organizations (MAO)—private organizations that offer one or more health benefit plans—propose to enter in the upcoming year. From 2013 through 2015, CMS's reviews accounted for less than 1 percent of all networks. To facilitate its review of these networks, CMS has established standardized data collection via an automated system. However, CMS does little to assess the accuracy of the network data in applications MAOs submit, even though the submissions contain the same data elements as in provider directories, which have been shown to be inaccurate in a number of government and private studies. Until CMS takes steps to verify MAO provider information, as outlined in federal internal control standards, the agency cannot be confident that MAOs meet network adequacy criteria.

For established provider networks, CMS does not require MAOs to routinely submit updated network information for review, but may learn of any adequacy issues through its broader oversight of MAOs. CMS recently required that MAOs disclose efforts to significantly narrow provider networks, allowing MAOs to determine when such disclosure is necessary. CMS also relies on complaints it receives to identify any problems related to network changes that are not otherwise identified. However, contrary to internal control standards, CMS does not measure ongoing MAO networks against its current MA criteria. Because a plan's providers may change at any time, CMS cannot be assured that networks continue to be adequate and provide sufficient access for enrollees until the agency collects evidence of compliance on a regular basis.

While CMS requires that MAOs give enrollees advance notice when a provider contract is terminated, the agency has not established information requirements for those notices and does not review sample notices sent to enrollees. This lack of scrutiny appears inconsistent with the agency's oversight of other Medicare beneficiary communications and with internal controls. Without a minimum set of required information elements and a check on adherence to them, the agency cannot ensure that MAO communications are clear, accurate, and consistent.

Why GAO Did This Study

MAOs contract with a network of providers to manage health care delivery to their enrollees. MAOs can initiate or terminate contracts with providers at any time for any reason. Recently, some MAOs have been narrowing their provider networks, prompting concerns about ensuring enrollee access to care and CMS's oversight of MAO compliance with network adequacy criteria.

GAO was asked to review how CMS ensures adequate access to care for MA enrollees. This report examines (1) how CMS defines network adequacy and how its criteria compares with other programs, (2) how and when CMS applies its criteria, (3) the extent to which CMS conducts ongoing monitoring of MAO networks, and (4) how CMS ensures that MAOs inform beneficiaries about terminations. GAO reviewed CMS and other guidance on network adequacy, federal regulations, and standards for internal control. GAO also interviewed CMS officials and representatives of medical associations and beneficiary advocacy groups, and analyzed CMS data on oversight of MAO provider networks for contract years 2013 through 2015.


The Administrator of CMS should augment oversight of MA networks to address provider availability, verify provider information submitted by MAOs, conduct more periodic reviews of MAO network information, and set minimum information requirements for MAO enrollee notification letters. HHS concurred with the recommendations.

Recommendations for Executive Action

Agency Affected Recommendation Status
Centers for Medicare & Medicaid Services To improve its oversight of network adequacy in MA, the Administrator of CMS should augment MA network adequacy criteria to address provider availability.
HHS concurred with this recommendation. As of August 2023, CMS has not included provider availability as part of its MA network adequacy criteria. While CMS has not updated these criteria, the agency described the various efforts it has taken related to provider availability, including examining MAO provider directories that document whether a provider is accepting new patients. Specifically, CMS stated in November 2020 that it has reviewed the accuracy of its own tools and MAO provider directories. In those reviews, CMS reported finding a number of variables affecting whether a provider is accepting new patients, noting that it is difficult for an MAO to capture this information in real time. As a result, CMS updated its provider directory policy to allow MAOs to include a notice instructing beneficiaries to contact a provider to determine the provider's status. CMS also stated that it encourages MAOs to use a national system to create and update provider directories but that the system does not include a data field related to whether a provider is accepting new patients. CMS also stated that it monitors complaints to identify access to care issues related to provider availability and that MAOs are provided an incentive by the CMS Star Ratings system to perform well on beneficiary surveys that, in part, ask about getting appointments and care quickly. As CMS has not included provider availability in its MA network adequacy criteria, the agency has not implemented this recommendation as of August 2023.
Centers for Medicare & Medicaid Services To improve its oversight of network adequacy in MA, the Administrator of CMS should verify provider information submitted by MAOs to ensure validity of the Health Services Delivery data.
HHS concurred with this recommendation, and noted in a January 2020 update that the agency has two methods by which it plans to ensure the validity of the Health Services Delivery data. First, CMS conducts MAO provider directory reviews to identify inaccuracies, which it then uses to verify errors in Health Services Delivery data as over 95 percent of MAOs reported using the same underlying data for both items. CMS reported that, from 2016 through 2018, it had reviewed provider directory sample data from 170 plans, which consisted of over 18,000 primary and specialty care providers at approximately 37,000 locations. CMS then provided MAOs with an opportunity to review and respond to the provider directory review findings. In a November 2020 update, CMS noted that it has temporarily suspended its provider directory reviews due to the COVID-19 pandemic. Second, CMS has encouraged MAOs to use a national system to obtain provider information, which could result in a single source for MAOs to update both provider directories and Health Services Delivery data. MAOs use of the system is voluntary and the extent to which MAOs are using the system is not clear. The agency has not yet implemented this recommendation as of August 2023.
Centers for Medicare & Medicaid Services To improve its oversight of network adequacy in MA, the Administrator of CMS should expand network adequacy reviews by requiring that all MAOs periodically submit their networks for assessment against current Medicare requirements.
Closed – Implemented
CMS took action to address our recommendation by instituting a network adequacy review process for contract year 2018 that expands its oversight to all MAOs. The expanded reviews under CMS's new process now occur separately from the MAO application process. Under this process, CMS requires each MAO to upload its full contract-level network for review on a rolling 3-year basis. In addition, MAOs that have triggering events (e.g., entering or expanding into a new service area, or a significant provider contract termination) require network adequacy reviews.
Centers for Medicare & Medicaid Services To improve its oversight of network adequacy in MA, the Administrator of CMS should set minimum requirements for MAO letters notifying enrollees of provider terminations and require MAOs to submit sample letters to CMS for review.
HHS concurred with this recommendation. In a September 2017 update, the agency stated that it had met the spirit of our recommendation by adding its best practice suggestions of what should be included in the written termination notice to the Medicare Managed Care Manual. However, as we noted in our report, those practices are not required, nor are the letters regularly reviewed. CMS reiterated its position in a November 2020 update, stating that MAOs have the knowledge and experience to notify enrollees without needing minimum requirements. CMS also stated that it does not have a process in place to routinely review sample letters but MAO letters it has received in the past have incorporated CMS's suggestions for making information clearer to enrollees. In October 2021, CMS provided documentation of the five MAO letters related to significant provider terminations it had examined in the 1-year period from August 2020 to August 2021. For three of the five letters, CMS required the MAO to make changes to its letter, in some cases to avoid potentially confusing information. Because CMS has not set minimum requirements or routinely required MAOs to submit sample provider termination letters, the agency has not implemented this recommendation as of August 2023.

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