Use of surplus proficiency test items
- Details
- Last Updated: Saturday, 27 September 2025 23:05
Content
Test items are sometimes available from proficiency testing (PT) providers after the completion of a PT round. The EURACHEM Proficiency Testing Working Group has produced an information leaflet to advise laboratories on benefits and limitations of surplus PT items.
This second edition is an editorial amendment to reference recent guidance on PT.
Availability
The second edition is currently available in the following languages. Links to selected translations of the first edition are temporarily maintained on this page (below) for convenience while translations of the second edition are prepared.
- Download English version [203 kB] (2022-07-30)1,2
- Download Bulgarian version [169 kB] (2025-09-27)
- Download Czech version [243 kB] (2023-09-20)
- Download French version [256 kB] (2023-09-20)
- Download German version [237 kB] (2023-09-20)
- Download Italian version [269 kB] (2024-01-15)
- Download Romanian version [253 kB] (2025-09-27)
- Download Spanish version [230 kB] (2023-10-17)
- Download Turkish version [187 kB] (2025-09-26)
Translation
Please consult the PT Working Group Chair if you would like to prepare a translation in your own language.
Previous editions
The first edition of this information leaflet can be found here, in our publication archive, in nine languages. Selected translations of the first edition are listed below for convenience pending translation of the second edition.
- Download Farsi version (1st ed.)
- Download Swedish version (1st ed.)
- Download Ukrainian version (1st ed.)
Notes
1. Dates show date of publication of the linked file on this website.
2. 2nd English edition first published 2022-07-30
A laboratory will occasionally have a poor performance in a PT scheme. When this occurs, the laboratory should acknowledge it, carry out an investigation and document a review of possible causes, even if it decides not to take any specific action. This leaflet, prepared by the EURACHEM 
The Eurachem Guide on “Selection, Use and Interpretation of Proficiency Testing (PT) Schemes” recommends participants to consider the statistical approach used by the PT provider when selecting a PT scheme. This leaflet is intended to help participants in quantitative PT schemes to better understand the statistical parameters that are used in the PT report to describe the distribution of results reported by participants.
All proficiency testing schemes include an assessment of laboratory performance. Most compare a laboratory result with an assigned value, and assess performance based on the difference and a criterion for successful performance. Often, this assessment also involves calculating a score for consistent interpretation across rounds and, sometimes, across PT schemes. But there are many different ways of determining an assigned value and setting a criterion for performance assessment, and there are several different scoring methods. 