Reference systems serve to establish metrological traceability in laboratory medicine. Once established, the aim is to maintain these systems in the long term in order to preserve the resulting increase in quality. This is not something to be taken for granted. The experience gained from horizontal and vertical links within the traceability hierarchy reveals both the strengths and weaknesses of the reference systems that have been established to date. It is therefore essential to understand how the components of the reference systems interact. The various stakeholders from the fields of metrology and laboratory medicine have to build networks to coordinate their activities and develop solutions in order to be able to use the existing systems in the future and also to develop new ones for quality assurance in laboratory medicine.
