The (K)ILO school project (Quality in Laboratory Education) is a yearly collection of proficiency tests (PT). Students in the (K)ILO project are required to devise their own measurement plan, covering all aspects of sample preparation and analysis and to report and defend their results before an external jury. This paper reports on the 2023 year’s project where mass fractions (g/kg levels) of copper, iron, magnesium and zinc in a feed premix material (BPT-MIN2022-KILO) were determined by the participants. The students’ PT results clearly show a big difference in overall performance, z scores and number of outliers, when the statistical approach depends on the assigned value (AV), derived from formulation or from consensus) and the standard deviation for proficiency testing (σpt) fixed or derived from algorithm A. As an example, the overall performance of the four parameters with the consensus method that was assessed as satisfactory is between the range 72 to 100

A summary of the working group discussions on proficiency testing (PT) and external quality assessment (EQA) held at the Eurachem Workshop, Berlin, Germany, 6–9 October 2014 is provided. The working groups covered a range of issues concerned with current practice and future directions: review of ISO/IEC 17043; user perspective of PT/EQA; sampling PT/EQA; the revised ISO 13528; PT/EQA in developing countries; and harmonisation of performance assessment in qualitative PT/EQA. Delegates from 64 countries attended the workshop, and this diversity of different backgrounds was represented on each of the working groups in order to capture a range of views and experience from a number of different measurement sectors. Working group representatives included PT/EQA providers, participants in PT/EQA schemes, end-users of PT/EQA results such as accreditation bodies and regulatory authorities, national measurement institutes, laboratory associations, universities and independent consultants from countries around the world.