Proficiency Testing (PT)


Proficiency testing (PT) is the testing of unknown samples and sending the results to a CMS approved PT program.

Regulated analytes are tests found in Subpart 1 of “Proficiency Testing Programs for Nonwaived Testing” in the CLIA regulations. PT IS REQUIRED for these tests. Refer to CLIA Brochure # 8 Proficiency Testing for a list of regulated analytes.

Unregulated analytes are tests not found in Subpart 1 of “Proficiency Testing Programs for Nonwaived Testing” in the CLIA regulations. PT IS NOT REQUIRED for these tests, however the lab must verify the accuracy of these tests twice a year. PT is not required for waived tests.

Unsatisfactory performance means the lab failed to attain the minimum satisfactory score for each analyte, test, subspecialty, or specialty for that particular PT event.

Unsuccessful performance means the lab failed to attain a satisfactory score for each analyte, test, subspecialty, or specialty for two consecutive or two out of three consecutive testing events.


Each laboratory is responsible to contact a CMS approved PT program and enroll for all regulated analytes.

PT enrollment and participation is required for each CLIA certificate. Enrollment in PT is per CLIA number not per site. If you have multiple sites under one CLIA number, all regulated analytes must be enrolled in the approved PT program for that certificate. If you have separate CLIA certificates for different sites you must enroll in PT for each site.

PT is not required for CLIA waived tests. Check the FDA website to determine if your tests are waived.

Accredited labs must also follow the proficiency testing requirements of your Accrediting Organization. This does not apply to cytology PT.

Cytology PT- Laboratories must ensure each person that examines gynecologic preparations is enrolled in a CMS approved Cytology PT program

Laboratories must remain enrolled in the same PT program for one year before changing to a different program.

If a lab adds a new regulated analyte to their test menu they must contact their PT agency to add that analyte as soon as possible.

If your laboratory performs the same test by two different methods you need to enroll in PT for the primary method.

How to Verify Accuracy of Unregulated Analytes

  • Split a patient’s specimen with another lab that offers the same test.
  • Enroll and perform PT on the test.
  • Do follow up sampling of the tests performed with a confirmatory test or another test.
  • Split specimens with a person who has demonstrated competency in examining the materials.
  • Enroll in a proficiency testing program that is not approved by CMS but covers the testing performed.
  • Additional Kodachromes could be rotated among the personnel examining the specimens.

Handling of PT Samples


Always treat PT samples as you do your patient samples. No special handling. Do not send PT samples out for reflex testing.

Keep copies of all of the following PT records for two (2) years: proof of enrollment, raw testing data, instrument print-outs, PT program scores (including attestation statements), print screens (if submitted electronically) and any corrective action.

Desk Review

When a laboratory obtains an unsuccessful PT participation score for two (2) events in a row or two (2) out of three (3) events written deficiencies are issued to the lab based on a surveyor desk review of the PT scores. The lab will have ten (10) days to respond back to the surveyor with a written acceptable plan of correction that will include proof of either re-training of staff or technical assistance. Once the surveyor accepts the plan of correction and supporting documentation the process is complete. The lab is still at risk for two more PT events.

In the event the lab receives an unsuccessful participation score for three (3) events in a row or three (3) out of five (5) events that lab’s participation scores will be sent to CMS for enforcement proceedings. The lab will be issued a statement of deficiencies directly from CMS. The lab must submit their plan of correction directly to CMS and their regional surveyor within ten (10) days of receipt. Enforcement can result in cease testing of the failed analyte, subspecialty or specialty.

For additional information refer to the CLIA Brochure #8 Proficiency Testing and CLIA Regulations. This information is not intended to replace or substitute the CLIA regulatory requirements. It is intended only to present the PT requirements in layman’s terms.