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Comprehensive Error Rate Testing (CERT)

Comprehensive Error Rate Testing (CERT)

The Centers for Medicare & Medicaid Services (CMS) calculates the Medicare Fee-for-Service (FFS) improper payment rate through the Comprehensive Error Rate Testing (CERT) program. Each year, CERT evaluates a statistically valid stratified random sample of claims to determine if they were paid properly under Medicare coverage, coding, and billing rules.

The fiscal year (FY) 2018 Medicare FFS program improper payment rate is 8.12 percent, representing $31.62 billion in improper payments, compared to the FY 2017 improper payment rate of 9.51 percent or $36.21 billion in improper payments (1). The table below outlines the improper payment rate and projected improper payment amount by claim type for FY 2018. The reporting period for this improper payment rate is July 1, 2016 -June 30, 2017.

Claim Type

Improper Payment Rate

Improper Payment Amount (2)



$31.62 B

Part A Providers (excluding Hospital Inpatient Prospective Payment System (IPPS))


$13.60 B

Part B Providers


$10.47 B

Hospital IPPS


$4.96 B

Durable Medical Equipment, Prosthetics, Orthotics, and Supplies


$2.59 B

All public reports produced by the CERT program are available through the "CERT Reports" link on the section navigation tray to the left. The improper payment rate is released annually in the Department of Health and Human Services (HHS) Agency Financial Report (AFR), which can be accessed through the HHS AFR link in the Related Links section at the bottom of this page.

(1) The national overall and hospital IPPS improper payment rates are adjusted for the impact of Part A to B rebilling of denied inpatient claims.  

(2) Columns may not sum correctly due to rounding.