Institute for Interlaboratory Studies

Spijkenisse, The Netherlands



iis organises all kinds of interlaboratory studies (ILS) on a professional basis:


Type of study Also known as
Proficiency Testing (PT) Interlaboratory comparison, laboratory evaluating study, round robin, cross check program, correlation program, co-operative trial, Ringversuch
Method validating studies Collaborative trial, collaborative test
Material characterising studies Preparation of reference materials


Besides the Institute's annual program with proficiency tests, tailor made studies are organised on request.


In all studies confidentiality is guaranteed. Test results, the performance (z-score), the test methods and any other information that is provided by a participating laboratory, is reported under a unique code. The relation between the code and the participant's name is only revealed to the laboratory itself. See the FAQ page for more details on the iis' PT program.






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