Inter-laboratory comparison
Introduction
Inter-laboratory studies/comparisons are performed with the aim of evaluating the extent of similarity in the results obtained by different laboratories using the same method
Inter-laboratory comparison study
The study typically consists of:
- Planning
- Selection/recruitment of laboratories
- Execution according the plan
- Statistical evaluation of results
Standards and guidelines
ISO 17025, chapter 5.6.2.1.2 Participation in a suitable program of
inter-laboratory comparisons is required where possible.
ISO 5725:1994(E), Accuracy (trueness and precision) of measurement
methods and results;
ASTM E 691–99, Standard Practice for Conducting an Interlaboratory
Study to Determine the Precision of a Test Method;
ASTM E 1301–95E1, Standard Guide for Proficiency Testing by
Interlaboratory Comparisons;
ISO Guide 43–1984(E), Development and operation of laboratory
proficiency testing;
Youden. W. J. Statistical Techniques from Collaborative Tests.
ELA G6. WELAC Criteria for Proficiency Testing in Accreditation.
ISO/REMCO N 231 revised January 1992: Harmonized Proficiency Testing
Protocol.
EN 932–6. Tests for general properties of aggregates – Part 6:
Definitions of repeatability and reproducibility
