VEQ: sfide attuali e prospettive future

AUTORI

ABSTRACT

Proficiency Testing/External Quality Assessment: Current Challenges and Future Directions

Proficiency testing or EQA is intended to verify on a recurring basis that laboratory results conform to expectations for the quality required for patient care. Key factors for interpreting EQA results are knowledge of the commutability of the samples used and the process used for target value assignment. A commutable EQA sample demonstrates the same numeric relationship between different measurement procedures as that expected for patients’ samples. Noncommutable EQA samples frequently have a matrix-related bias of unknown magnitude that limits interpretation of results. EQA results for commutable samples can be used to assess accuracy against a reference measurement procedure or a designated comparison method. In addition, the agreement of the results between different measurement procedures for commutable samples reflects that which would be seen for patients’ samples. EQA results for noncommutable samples must be compared to a peer group mean/median of results from participants who use measurement procedures that are expected to have the same or very similar matrix-related bias. Peer group evaluation is used to asses whether a laboratory is using a measurement procedure in conformance to the manufactur er’ s specifications and/or in conformanc e t o ot her labor atori es u sing the same technology. A noncommutable EQA sample does not give meaningful information about the relationship of results for patients’ samples between different measurement procedures. EQA provides substantial value to the practice of laboratory medicine by assessing the performance of individual laboratories and, when commutable samples are used, the status of standardization or harmonization among different measurement procedures.

BIBLIOGRAFIA