Evaluation of the CMS-HCC Risk Adjustment Model: Final Report

March 2011 The Center for Medicare and Medicaid Services (CMS) has used the CMS hierarchical condition categories (CMS-HCC) model since 2004 to adjust Medicare capitation payments to Medicare Advantage health care plans for the health expenditure risk of their enrollees.  This report on the accuracy of the model was mandated by the Patient Protection and Affordable Care Act of 2010. It contains three major sections: a primer on the CMS-HCC model and more generally the use of risk adjustment within a health insurance market; an evaluation of the CMS-HCC model, including an evaluation of the predictive accuracy . . .