Clinical Laboratory Improvement Amendment of 1988
General Information

Congress passed the Clinical Laboratory Improvement Amendments (CLIA) in 1988 establishing quality standards for all laboratory testing to ensure the accuracy, reliability and timeliness of patient test results regardless of where the test was performed. The objective of the CLIA program is to ensure quality laboratory testing. Although all clinical laboratories must be properly certified to receive Medicare or Medicaid payments, CLIA has no direct Medicare or Medicaid program responsibilities.

A laboratory is defined as any facility which performs laboratory testing on specimens derived from humans for the purpose of providing information for the diagnosis, prevention, treatment of disease, or impairment of, or assessment of health. CLIA is user fee funded; therefore, all costs of administering the program must be covered by the regulated facilities, including certificate and survey costs.

The final CLIA regulations were published on February 28, 1992 and more recently updated in April 2003, and are based on the complexity of the test method; thus, the more complicated the test, the more stringent the requirements. Three categories of tests have been established: waived complexity, moderate complexity, including the subcategory of provider-performed microscopy (PPM), and high complexity. CLIA specifies quality standards for proficiency testing (PT), patient test management, quality control, personnel qualifications and quality assurance for laboratories performing moderate and/or high complexity tests. Waived laboratories must enroll in CLIA, pay the applicable fee and follow manufacturers' instructions. CMS issues 4 different CLIA certificates based on the type of testing performed by the laboratory.

Certificate of Waiver
This certificate is issued to a laboratory to perform only waived tests.

Certificate for Provider-Performed Microscopy Procedures (PPMP)
This certificate is issued to a laboratory in which a physician, midlevel practitioner or dentist performs no tests other than the microscopy procedures. This certificate permits the laboratory to also perform waived tests.

Certificate of Registration
This certificate is issued to a laboratory that enables the entity to conduct moderate or high complexity laboratory testing or both until the entity is determined by survey to be in compliance with the CLIA regulations.

Certificate of Compliance
This certificates is issued to a laboratory after an inspection that finds the laboratory to be in compliance with all applicable CLIA requirements.

Certificate of Accreditation
This is a certificate that is issued to a laboratory on the basis of the laboratory's accreditation by an accreditation organization approved by HCFA.

The Centers for Medicare & Medicaid Services (CMS) is charged with the implementation of CLIA, including laboratory registration, fee collection, surveys, surveyor guidelines and training, enforcement, approvals of PT providers, accrediting organizations and exempt states. The Centers for Disease Control and Prevention (CDC) is responsible for the CLIA studies, convening the Clinical Laboratory Improvement Amendments Committee (CLIAC) and providing scientific and technical support/consultation to DHHS/CMS. The Food and Drug Administration is responsible for test categorization.

To enroll in the CLIA program, laboratories must first register by completing an application, pay fees, be surveyed, if applicable, and become certified. CLIA fees are based on the certificate requested by the laboratory (that is, waived, PPM, accreditation, or compliance) and, for moderate and high complexity laboratories, the annual volume and types of testing performed. Waived and PPM laboratories may apply directly for their certificate as they aren't subject to routine inspections. Those laboratories which must be surveyed routinely; i.e., those performing moderate and/or high complexity testing, can choose whether they wish to be surveyed by CMS or by a private accrediting organization. The CMS survey process is outcome oriented and utilizes a quality assurance focus and an educational approach to assess compliance.

Further information relating to the CLIA requirements and programs can be accessed from the CMS CLIA homepage: Information available through this site includes, but is not limited to:

  • Final CLIA regulations
  • Interpretative guidelines relating to the final regulations
  • Text Complexity data-base
  • List of approved Proficiency Testing Programs
  • Certificate fee schedule
  • Web connecting site for downloading CMS forms

This information is provided by the Clinical Laboratory Program within the Department of Public Health.