Failed CLIA Proficiency Testing: What to Do Next
Under CLIA, failing one proficiency testing (PT) event is unsatisfactory performance. Failing the same analyte, or the overall event score, in two consecutive events or two of three consecutive events is unsuccessful performance, and CMS can sanction the lab. Every failure needs documented remedial action, and you must keep that documentation for two years.
Last reviewed Oct 2026 · By Sound Lab Consultants CLIA team · General information, not legal advice. Confirm against the current eCFR and your notice letter.
Key facts and official sources
Nonwaived labs must successfully participate in CMS-approved PT for each specialty, subspecialty and analyte they are certified for. Source: 42 CFR 493.803
Two consecutive failures, or two of three consecutive failures, is unsuccessful performance. Source: 42 CFR 493.837 (the same pattern applies across Subpart H)
PT samples must be tested like patient samples. Labs may not communicate about results before the due date or refer PT samples to another lab. Source: 42 CFR 493.801
Reinstatement after a PT-related sanction requires two consecutive satisfactory events. Source: 42 CFR 493.807
What is the difference between unsatisfactory and unsuccessful PT?
Unsatisfactory: One testing event below the passing score for an analyte, or for the overall event Remedial action must be taken and documented, and the records kept for 2 years
Unsuccessful: Unsatisfactory for the same analyte, or overall, in 2 consecutive events or 2 of 3 consecutive events Condition-level noncompliance with §493.803 (surveyors cite tag D2016, Successful Participation). CMS may impose sanctions
A missed event, or results returned after the program's deadline, scores zero for that event. Missing an event counts as unsatisfactory performance, so it can contribute to unsuccessful performance.
What must a PT corrective action include?
CLIA requires the lab to "undertake appropriate training and employ the technical assistance necessary to correct problems" and to document remedial action. A defensible record covers these steps:
Confirm the failure. Check for clerical errors: transcription, units, method code, instrument code and late submission.
Look back at patient results. Decide whether patient results reported around the event were affected, and correct any reports that were.
Find the root cause. Typical categories are clerical, method or calibration, QC, reagent or lot, specimen handling, and staff competency.
Fix it. Recalibrate, repair, change the lot, revise the procedure or retrain, as the cause requires.
Verify the fix. Retest the retained PT material or other samples of known value, and review QC and calibration verification.
Review and sign off. The lab director or technical consultant/supervisor reviews and signs the investigation.
Monitor. Watch the next events and QC trends to confirm the problem is resolved.
Keep the PT reports, the signed attestation and your investigation together. CLIA requires PT records to be kept for at least two years.
What can CMS do after unsuccessful PT?
For an initial unsuccessful performance, CMS may direct the lab to undertake training of its personnel, obtain technical assistance, or both, instead of imposing sanctions (§493.803(c)). That option is not available if any of the following applies:
the failure poses immediate jeopardy
the lab can't show it has corrected the problem
the lab has a poor compliance history
Otherwise, CMS can impose principal sanctions such as a limitation of the certificate for the failed analyte, which means you must cease testing for that analyte. It can also impose alternative sanctions: a directed plan of correction, state onsite monitoring or a civil money penalty (§493.1806). PT failures are often cited together with lab director tags, because the director is responsible for the PT program. See our CMS-2567 plan of correction guide.
How does a lab get reinstated after a PT sanction?
Under the current rule, the lab must show sustained satisfactory performance on two consecutive PT events before CMS will consider reinstatement for the failed specialty, subspecialty or analyte. The current rule also sets a minimum period of at least six months (§493.807).
Proposed, not in effect: the October 8, 2026 CLIA proposed rule (CMS-3478-P) would rescind the mandatory waiting period in §493.807(b). It would also remove the phrase "one of which may be on site" so that labs could use on-site or off-cycle PT for the reinstatement events. Current rules apply until a final rule is published. See our CLIA proposed rule 2026 summary.
How do you avoid PT handling violations?
Test PT samples with your regular patient workload, using your routine methods and the staff who normally run the test. Test them the same number of times you test patient samples.
Have the analyst and the lab director sign the attestation.
Don't discuss results with other labs, or between your own sites, until after the reporting deadline.
Never send PT samples to another lab for testing you are certified to perform. CMS can revoke the certificate of a lab that intentionally refers PT samples (§493.801(b)(5), §493.1840(b)).
Frequently asked questions
Is one failed PT event a CLIA violation?
One failed event is unsatisfactory performance. It requires documented remedial action, but it is not unsuccessful performance on its own. A second failure for the same analyte in the next event, or in two of three consecutive events, makes it unsuccessful.
How long do we keep PT remedial action records?
At least two years from the date of the PT event. That covers PT reports, attestations and remedial action records.
Can CMS stop us from testing an analyte after PT failure?
Yes. CMS can limit the CLIA certificate for that analyte, specialty or subspecialty. You must stop patient testing for it until CMS reinstates you.
Does unsuccessful PT affect our lab director?
Often. The director is responsible for PT enrollment, review and corrective action, so surveyors may also cite director responsibilities.
Do waived tests need PT?
No. The Subpart H PT requirements apply to nonwaived testing. Waived tests follow the manufacturer's instructions.
Get help with a PT failure
Sound Lab Consultants investigates PT failures, writes corrective action records and plans of correction, and provides lab director and technical consultant coverage while you recover.