CMS’ Wasteful and Inappropriate Service Reduction (WISeR) Model launched as a pilot in January 2026, with an intended goal to curb fraud, waste, and abuse through a new AI-assisted prior authorization and medical necessity review process for a select group of traditional Medicare services. Since then, the WISeR Model has faced implementation challenges and legislative pressure, but it remains in effect. At the same time, we continue to see an increase in payors’ use of AI and technology in the revenue cycle and prior authorization space.
In this article, we explore implementation challenges for providers under the model, concerns from legislators and other key stakeholders about the model’s methodology, and how providers can adapt to AI-supported review processes.
What Implementation Challenges Have Providers Faced Under the WISeR Model?
Based on our experience with clients, common challenges for providers impacted by the WISeR Model include:
- Understanding Requirements: Many providers have experienced confusion regarding the “voluntary” nature of the WISeR Model and whether authorizations are required for the services in scope. Although providers can technically bypass pre-service prior authorization, claims submitted without authorization are generally subjected to prepayment medical review, which requires a similar approval workflow that may include medical record submission.
- Navigating Complex Workflows: WISeR Model vendor participants have established new portals for submission of authorization and documentation requests. Providers have experienced challenges with navigating these new portals, adjusting to contingency workflows when portals were down, and understanding when to use the portals versus working directly with their Medicare Administrative Contractor (MAC). The model has also forced some organizations to establish traditional Medicare prior authorization workflows for services or provider groups for which no previous requirements or workflows existed.
CMS and vendor participants have provided guidance, but we continue to hear from clients about their challenges in the model.
What Concerns Have Stakeholders Expressed About the WISeR Model?
Concerns exist around WISeR Model governance, oversight, and accountability.
- AI Governance: While CMS has emphasized that WISeR relies on existing Medicare coverage requirements and requires clinician review of nonapproval decisions, provider groups, including the American Hospital Association,1 have expressed concerns about how AI is incorporated into the review process and how these tools are trained, validated, monitored, and governed for consistent use.
- Transparency & Program Oversight: Providers have also expressed concerns over how WISeR vendors are selected, how performance is monitored and incentivized, and how review methodologies are structured. Provider advocates have noted2 that several selected vendors have existing business relationships with commercial health plans or have received investments from organizations affiliated with health plans or other payor entities. In addition, the model does not include a mechanism for public vendor performance reporting or transparent formulas explaining how vendors are compensated. CMS has stated the payment methodology is a novel approach based partially on reducing payment for unnecessary or noncovered services, but publicly available details are limited.
What Legislative Challenges Has the WISeR Model Faced?
In May 2026, the U.S. Government Accountability Office (GAO) concluded that the WISeR Model notice qualifies as a “rule” under the Congressional Review Act, and therefore, CMS should have submitted the model to Congress for review before implementation, which it did not do. Senate Democrats introduced a disapproval resolution attempting to strike down the WISeR Model, but the resolution ultimately failed to pass a floor vote in July 2026. The WISeR Model is currently still in effect, but it continues to face active legal pressure and potential lawsuits over its transparency and procedures.
What’s Next for the WISeR Model & AI-Supported Prior Authorization?
Whether the WISeR Model will ultimately succeed in its intended mission to reduce fraud, waste, and abuse remains to be seen. However, we do anticipate payors’ AI use will continue to increase regardless of the success of the WISeR Model pilot. Providers should establish strong revenue cycle workflows and develop the ability to adapt to an evolving regulatory and technology landscape to help position themselves for success in the future.
How Forvis Mazars Can Help with the WISeR Model
Our revenue cycle team helps organizations adapt to regulatory changes like the WISeR Model and execute performance improvement initiatives that help them maintain financial discipline. If you have questions or would like assistance navigating WISeR Model requirements, please reach out to our team today.