The proficiency test is a tool to determine the influence of parameters which may vary between individual laboratories, it does not represent a substitute for the calibration procedure, the use of calibrated equipment is taken for granted.

The participation in the proficiency test scheme is open for all testing laboratories with a specific experience in chosen methods, the extent of the method selection is free.

The proficiency test is run and evaluated according to the ISO 17043. So called "z-score" is the measure of the laboratory performance.

The "z-score" gives an information about the bias of the laboratory result and can be used as a documentation of the lab performance for third parties and supervisory bodies.

Two different testing samples will be distributed for each method. This enables a differentiation if the bias of the particular laboratory results rather from a systematic error or from a random error.

Additionally, the reported data is utilized for the calculation of the repeatability (r) and reproducibility (R) of the test results (test method precision) on two levels.

The participants can utilize this evaluation for the calculation of the measurement uncertainty of the particular test method. In the Test Scheme Report, an advice will be given how to calculate the measurement uncertainty.

To establish a sufficient significance of the statistical evaluation, the inter-comparison test concerning a particular method will only be run if the internally set minimum number of participants will be achieved (≥7).

The identity of the participants is handled confidentially and the anonymity of the results is safeguarded by the allocation of the LabCodeNumbers to the participants.