INTERLABORATORY STUDIES AS A TOOL FOR MANY PURPOSES - PROFICIENCY TESTING, LEARNING EXERCISES, QUALITY-CONTROL AND CERTIFICATION OF MATRIX MATERIALS

Interlaboratory studies are collaborative exercises by laboratories to assess or improve the quality for their measurements. They are an important aspect of quality control and quality assurance systems which should be set up by all testing laboratories. They are efficient tools for investigating the method and the laboratory performance and also to certify reference materials. They can be applied with a research or teaching objective but they can also be used to assess the performance of a normalized method or the ability of a laboratory to perform a given task. As such they are a complementary aspect of accreditation audits.