'Allowable Limits of Performance' for External Quality Assurance Programs - an Approach to Application of the Stockholm Criteria by the RCPA Quality Assurance Programs

摘要

External quality assurance (EQA) has been described as the 'fifth pillar' of laboratory standardisation, added to the four pillars of reference materials, reference methods, reference laboratories and traceable reference intervals and decision points.1 One vital component of an EQA program is to provide criteria to allow participating laboratories to assess their performance. These criteria, also described as quality standards, may be based on statistical comparison with peers, expert opinion, clinical need or other criteria. In Australia, the RCPA Quality Assurance Programs (RCPAQAP) quality standards are known as the Allowable Limits of Performance (ALP) and are used to assist with interpretation of all numerical QAP results in the program. The stated goal of these limits is that they are clinically based to provide warning of clinically important changes in assay performance. As these limits were derived some years ago2 it is appropriate to review them. This document describes the assessment and implementation of a hierarchical approach to setting quality standards for EQA programs using the approach used by the RCPAQAP Chemical Pathology as an example.