Periodic verification of results' comparability between several analyzers: experience in the application of the EP31-A-IR guideline.

The EP31-A-IR guideline proved to be useful for periodic verification of results' comparability. However, it must be considered that, to be practicable, it may require to adjust the acceptance criteria in accordance to the analytical performance of the available technology; as well as the number of analytical measurements conforming to the laboratory resources.