An Interlaboratory Comparison is a structured approach to evaluating and improving the quality of analyses carried out by different laboratories.

It is based on three key stages:

• Organization and execution of an analytical campaign on homogeneous, stable samples, distributed to all participating laboratories

• Collection and statistical processing of the analytical results obtained

• Comparative analysis of analytical performance

Objectives of the Interlaboratory Comparison:

• Evaluate the analytical performance of participating laboratories using the Z-score

• Assist laboratories in monitoring and controlling their measurement uncertainty using the Zeta-score