The testing process should parallel flow of a patient specimen testing and be reflective of the total testing process, including:
- General laboratory systems
- Pre-analytic systems
- Analytic systems
- Post-analytic systems
The following guidelines should be considered when performing PT:
- Testing personnel should have been previously determined to be competent to perform required testing.
- All quality control, instrument maintenance, calibrations, and additional manufacturer-required steps must be current and completed as per recommended schedule.
- PT samples are examined, handled, and tested by testing personnel using the laboratory’s routine methods of analyte testing with routine workload.
- Primary patient testing method for the analyte being evaluated should be used for evaluating the PT samples. Secondary instruments should be evaluated with an alternate PT method. It is not acceptable to order a second kit.
- A single testing personnel may not test the same set of samples at multiple institutions.
- Multiple testing personnel qualified for test performance have PT materials rotated as per regulatory requirements
- If a PT sample exceeds the analytical measurement range (AMR) of the assay, it must be tested and reported in the same manner as a patient sample and as per institution policies/procedures. This includes dilution and repeat testing, as well as the use of “greater than."
- When the result obtained for a PT sample requires additional reflex examinations (as does a patient sample), the laboratory should only perform the additional examinations on PT samples as per institution specific policies/procedures and when specifically instructed to do so by the PT provider.
- Regardless of institution specific policies/procedures, samples should never be forwarded or referred to any other laboratory for analysis. If this is institution protocol, the laboratory may select an appropriate response from options provided by the PT provider.
- All samples should be retained and stored as per the sample storage guidelines provided by the PT provider.
- When PT materials are not available, or a secondary test method is in place for a methodology, the laboratory is responsible for establishing an alternative assessment plan (AAP) to verify the acceptability of test performance.
