Proficiency testing under CLIA is no joke.
Failed tests lead to costly downtime for equipment and personnel as labs troubleshoot to find the source of an error. In the case of proficiency testing (PT), failures lead to time invested in corrective-action measures, and in the worst case, cease-testing directives from regulatory authorities. A failed CLIA proficiency test — multiple failures, especially — is the ultimate black mark not only on the career of a lab director but on the reputation of a clinical lab.
The key to CLIA confidence is the same simple approach you took to ace your exams back in college: preparation. If you run your assays through their paces on a regular basis, and you use high-quality third-party controls to root out any weak points in your testing protocol and train your lab staff, CLIA proficiency testing will be a breeze.
How Does CLIA Proficiency Testing Work?
Perhaps the best source of information on CLIA proficiency testing is the federal Department of Health and Human Services’ brief guidebook, “Proficiency Testing and PT Referral: Dos and Don’ts.” Check there for complete details. What follows is a basic overview.
Clinical labs must participate in an approved proficiency testing program for each non-waived test they provide. Non-waived tests include common lab offerings such as hepatitis B, HIV, and syphilis assays. (A complete list is available in the guide linked to above.)
Waived tests do not have to undergo proficiency testing, but the Department of Health and Human Services says, “Enrolling in a PT program and performing PT on your waived test(s) will provide you with an excellent indication of the accuracy and reliability of your waived test results thus improving the quality of the testing you provide to your patients.”
Once enrolled in a PT program, your lab will receive samples on a scheduled basis. According to CLIA, a lab must treat proficiency testing samples the same as any other human sample. One key difference, however, is you may not refer a proficiency testing sample to another lab.
In other words, you must test the proficiency sample as you would any other patient sample you receive. You will report the result to your PT program and the program grades the result according to the CLIA grading criteria. Your PT program will send your lab a report of your score.
What Are the CLIA Grading Criteria?
For most of the non-waived tests on the CLIA list, you will receive five samples from your PT program. You must run the samples for each assay and report the correct result four out of five times. If you fall short of this 80 percent threshold, it’s considered a failure.
You can easily see how your lab measures up, as your PT program will send you a report that compares your lab’s performance to that of other labs.
The Department of Health and Human Services points out that a passing grade of 80 percent should not be cause for laxity. A score of 80 percent means one out of five samples was outside the acceptable range of results. Despite the passing grade, you should still investigate to find what caused the failure and document your findings.
What Are the Consequences of Failing Proficiency Testing?
If your lab fails one proficiency test, you have an opportunity to redeem yourself. You must take remedial action, according to CLIA. That includes:
- Determining the cause of the error and correcting it.
- Documenting your actions.
- Addressing any patient results you reported during the period your PT was unsatisfactory. (You may have to rerun tests.)
- Continually monitoring the performance of the assay using quality control materials.
If the same assay fails two PT events in a row, or two out of three tests, you will be required to shut down that assay until you can discover the source of the failure, correct it, and demonstrate that you fixed the problem with two consecutive successful tests. Also, if you are required to cease testing, your Medicare and Medicaid reimbursement will be suspended or limited for six months, as will your CLIA certificate.
And, your failure will not go unnoticed. The Centers for Medicare & Medicaid Services publishes an annual laboratory registry that lists labs that have been sanctioned that year, including for unsuccessful PT.
How Can Your Lab Avoid PT Failure?
Many things can lead to an inaccurate test result. Sample mix-ups, putting the barcode on the wrong tube, clerical errors, and failure to follow the instructions outlined in the assay package insert are just a few of the more mundane reasons.
Other times, the failure may be the result of the assay itself. The assay may fail to detect a weak positive, for example.
If it’s not already clear, the strong-positive controls provided by assay manufacturers won’t be enough for a CLIA-proof quality control program. You need to run independent controls daily, near the assay’s cutoff.
(Start your QC overhaul with our recent article, “4 Best Practices for QC in a Clinical Testing Lab to Ensure Accurate Results.”)
Third-party controls are also essential for training your staff and monitoring their performance to prevent the type of inconsistencies that can result in CLIA testing failure.
Be Confident for CLIA
A strong quality-control program, based on the use of reference materials with known characteristics, can help alleviate uncertainty about CLIA.
For more tips on improving accuracy at your clinical lab, get your free copy of our guide, “Best Practices for Clinical Labs: Strategies for Implementing a Best-in-Class Quality Control System.”
