Validation of measurement capabilities

The best measurement capabilities (BMCs) of laboratories are usually described at the Accreditation Certificates, for the calibrations they perform. The evaluation of these BMCs is carried out also by interlaboratory comparisons (ILCs), the proficiency testing schemes as described by the ISO Guide 43 and ISO 13528 standard. The National Metrology Institutes traditionally organize the ILCs for the National Accreditation Boards, providing the travelling standards, the reference(s) value(s) and the statistical analysis of the laboratories results. The goal of this article is to discuss the existing approaches for evaluation of ILCs and propose a basis for the validation of laboratories BMCs.