Examining the Potential Impact of Medicare’s New WISeR Model WISeR Expands the Use of Prior Authorization in Traditional Medicare at a Time of Increasing Scrutiny Authors: Alex Cottrill, Jeannie Fuglesten Biniek, Juliette Cubanski, Tricia Neuman, and Misha Segal Published: Feb 10, 2026

https://www.kff.org/medicare/examining-the-potential-impact-of-medicares-new-wiser-model/?utm_campaign=KFF-Medicare&utm_medium=email&_hsenc=p2ANqtz-8wu5YS0QXFKI87WJrZi9O20OhMBvRL3nJHQjQef9h_DyZX89JNs1EY_O7DhpVTvP9PFtfTgufAOURD4RUFjfBP_6tfaQ&_hsmi=402967619&utm_content=402967619&utm_source=hs_email KFF Examines a Trump Administration Initiative to Expand the Use of Prior Authorization in Medicare A KFF analysis examines an initiative from the Center for Medicare & Medicaid Innovation (CMMI) to establish new prior authorization requirements in traditional Medicare, called the Wasteful and Inappropriate Service Reduction (WISeR) model. Prior authorization, which is rare in traditional Medicare but widely used by insurers that offer Medicare Advantage plans and private commercial plans, aims to reduce wasteful or inappropriate utilization of health care services and the associated health care spending. But it also can lead to delays and denials of needed care, uncertainty for patients, and administrative costs and hassles for health care providers. CMMI’s WISeR model, launched on January 1, tests the use of technologies, such as artificial intelligence, to review the appropriateness of select Medicare-covered services in six states over a six-year trial period. The new KFF analysis explores the model’s potential impact by examining recent spending and utilization trends in traditional Medicare for services selected for prior authorization review. Findings suggest the impact of the model is likely to be modest in its first year. That is because the services targeted account for a small share of total Part B spending in traditional Medicare, and because the vast majority of service spending and growth the model aims to address is accounted for by a single service category (skin substitutes), which the Centers for Medicare & Medicaid Services has simultaneously targeted with recent changes to payment policy.