Table 1.

Main activities of organizations and groups in establishing metrological traceability.

Organization/group involved in establishing traceabilityActivities/responsibilities of organization/groupCoordinating organizations
National metrology institutes• Realization of SI unitsConférence Générale des Poids et Mesures
• Calibration and measurement capabilities on the highest metrological level
• Reference materials with formal certificate
Reference (calibration) laboratories• Reference measurement servicesJoint Committee for Traceability in Laboratory Medicine (Bureau International des Poids et Mesures, International Federation of Clinical Chemistry and Laboratory Medicine, International Laboratory Accreditation Cooperation)
• Realization of non-SI units (i.e., IU as defined by WHO)Reference laboratory networks
• Value assignment to reference materials, calibration materials, and patient samples used for trueness control and calibration
• Accuracy assessments of measurement procedures and laboratories
Routine testing laboratories• Value assignment to patient samplesNational entities
• Calibration of routine measurement procedures