The Lewin Group helps policymakers design, implement, and evaluate Medicare policies and programs, and helps health plans and providers understand and adapt to Medicare policies.

Medicare is the nation’s largest health insurance program, covering more than 40 million Americans. The Lewin Group offers specialized expertise in Medicare policy, a longstanding relationship with the Centers for Medicare & Medicaid Services (CMS), and a 30-year history of policy analysis involving federal programs in general and Medicare in particular. Several members of The Lewin Group staff were former CMS employees or employees of other federal government programs.

Our work is designed to help the Medicare program reduce its costs, pay providers fairly, and ensure that services are delivered more efficiently and effectively.


The Lewin Group helps the federal government, providers, and health plans analyze Medicare policy proposals, design and evaluate programs, and assess performance. It brings the provider and plan perspective in its assistance to the government, and insight and understanding of Medicare policies in its assistance to plans and providers.

Policy Analysis and Modeling
  • Analyze CMS provider payment methodologies
  • Evaluate financial and operational impacts of proposed policy changes
  • Study quality performance measurement and pay-for-performance programs
Program Design and Evaluation
  • Design Medicare risk and incentive programs
  • Develop and evaluate demonstration programs
  • Assess payment integrity
Performance Assessment
  • Evaluate beneficiary utilization and satisfaction
  • Design, deliver, and evaluate provider education and training
  • Conduct feasibility and cost/benefit studies

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CMS Program Integrity

Payment error rate measurement (PERM) and comprehensive error rate testing (CERT)

In the mid-1990s, we helped CMS develop the concept of statistically sampling and then reviewing sampled paid claims for errors to estimate the rate of improper payments in Medicare. We then extended the methods to Medicaid. CMS uses the programs to satisfy the requirements of the Improper Payments Elimination and Recovery Act (IPERA). Today, we are the statistical contractor for both CERT (Medicare) and PERM (Medicaid) and have been engaged in both programs since their inception.

These programs are highly visible across the executive branch and Congress. CMS uses them to monitor progress in reducing payment error rates.

  • The results of CERT and PERM achieve high visibility across the executive branch and Congress, and they are used to help guide CMS, Medicare Authorized Contractors and the states’ error rate reduction efforts.
  • These reports help fulfill the goals of the Improper Payments Elimination and Recovery Act (IPERA).
  • CMS and the states act to reduce errors based on the findings of CERT and PERM.
  • Changes in the CERT and PERM error rates over time is a primary measure of the progress made in reducing improper payments.

"Throughout the engagement, Lewin consultants listened to us and delivered superb analyses and thoughtful guidance–not canned solutions.