The Clinical Laboratory Improvement Amendments (CLIA) regulate laboratory testing and require clinical laboratories to be certified by the Center for Medicare and Medicaid Services (CMS) before they can accept human samples for diagnostic testing. Laboratories can obtain multiple types of CLIA certificates, based on the kinds of diagnostic tests they conduct.

Three federal agencies are responsible for CLIA – Each agency has a unique role in assuring quality laboratory testing.

1. The Food and Drug Administration (FDA),
2. Center for Medicaid Services (CMS), and
3. Centers for Disease Control and Prevention (CDC).