Proficiency Testing (PT) is one form of external assessment of laboratories to ensure their ability to perform to the level of competence and quality required.
Originally designed to challenge laboratories in a form of interlaboratory comparison (Belk WP, Sunderman FW. A survey of the accuracy of chemical analyses in clinical laboratories. Am J Clin Pathol. 1947 Nov;17(11):853-61) proficiency testing has become more an ongoing measure of laboratory quality performance. It is a tool by which customers and other interested parties (including, but not limited to regulators, laboratory accreditation bodies) can be assured of competence not only in the technical aspect of laboratory performance but also in the much broader measures of relevancy, customer service, and response of error and improvement.
Proficiency Testing, especially as it is used in clinical laboratory practice is sometimes referred to as External Quality Assessment (EQA or PT/EQA).
In some disciplines PT/EQA, for example in clinical chemistry, is provided almost exclusively in a quantitative format, whereas in others, in particular Microbiology and Anatomic Pathology have many elements of a more qualitative and semi-quantitative nature.
Programs such as Clinical Microbiology Proficiency Testing (CMPT) provide an ongoing service for assessments at regular intervals rather than as a one-off challenge.
To meet the needs of true performance assessment, CMPT provides samples that closely mimic typical samples in appearance and performance. CMPT also uses a broader range of assessment tools to measure performance across the broad range of the path of workflow within the range of laboratory performances
PT assessment tools to measure performance across the path of laboratory workflow
| Pre-Examination | Examination | Post-Examination | Peri-Examination |
|---|---|---|---|
| Sample Collection Sample Requisition Sample Labeling Sample Transport Sample Receiving Sample Accession | Report Accuracy Report Precision | Report Content Accuracy Report Relevancy Commentary - Cautionary notes - Informative notes - Notification - Measurement Uncertainty | Safety Quality Control Customer Monitoring |
| Simulated samples Reverse samples Paper Challenges Video Challenges | Simulated samples evaluated against referee validated target values. | Report Evaluation against committee determined clinically appropriate expectations | Paper Challenges Video Challenges |
In some jurisdictions, PT/EQA is a regulated program and requires external evidence of quality and performance. This is not the case in Canada. Regardless, CMPT ensures its own quality through regular certification of its Quality Management system to ISO9001:2008/2015, and through accreditation to ISO/IEC 17043:2010 Conformity assessment — General requirements for proficiency testing
