Analytical quality specifications for reference methods and operating specifications for networks of reference laboratories. discussion paper from the members of the external quality assessment (EQA) Working Group B1) on target values in EQAS.

The aim of the Working Group was to describe guidelines for the establishment of networks of reference laboratories. The need for such networks to achieve an accuracy-based uniform measurement system with traceability of results of analytical systems/test-kits to the true value is outlined. Criteria for analytical quality specifications, which are related to the ultimate purpose of the reference method and thereby to the objectives of the networks, are emphasized. The group recommends the use of two models: one based on specifications for routine methods, which are dictated by the biological variations of the respective analytes, the second respecting the analytical state-of-the-art of reference methodology. Further, the group presents operating specifications for networks that guarantee the continuous performance of reference method measurements whilst maintaining a uniform and stable level of quality.