Proficiency Testing (PT) Requirements and Evaluation
What this domain tests
Proficiency testing (PT) evaluates whether a laboratory can produce acceptable results on unknown samples. The exam tests required participation, handling, scoring, and consequences of failure.
Core rules
- Laboratories must participate in PT for each regulated analyte they test, using the same method and personnel as patient testing.
- PT samples must be tested like patient specimens; laboratories must not refer PT samples to another laboratory or share results.
- Successful performance is generally 80% or better for each analyte. An unsuccessful event is a score below the threshold for an analyte; two consecutive unsuccessful events for the same analyte can lead to sanctions.
- The laboratory director must review and sign PT results. Records are retained for two years.
- Failure to participate is treated as failure.
Worked example
A laboratory scores 75% on glucose in the spring event and 78% on glucose in the fall event. Reasoning: each event is unsuccessful for glucose because both are below 80%. Two consecutive unsuccessful events for the same analyte create exposure to CLIA enforcement, including a plan of correction or stronger sanction. If the fall score had been 90%, the consecutive-failure trigger would not be met.
Traps
Averaging scores across analytes and calling it passing. Testing PT samples twice or sending them out. Letting a different method or non-routine staff handle PT. Forgetting director signature. Missing an analyte because it is 'only' a secondary test.