Guidance Document for the organisation of Proficiency Tests by  NRLs National Reference Laboratories (National Reference Laboratories)(National Reference Laboratories ) for national networks, including partial outsourcing

One of the tasks of a National Reference Laboratory ( NRL National Reference Laboratorie (National Reference Laboratorie)(National Reference Laboratory )) is to organize, where appropriate, Proficiency Tests (PTs) for the national network of designated official laboratories (OLs) it coordinates, according to Regulation ( EU Europese unie (Europese unie)(Europese unie)) 2017/625 (article 101) [link].
For different reasons (too small or too large size of the network, economic aspects, availability of human resources etc.), some NRLs outsource (parts of) these PTs.
The five EU Reference Laboratories (EURLs) on Campylobacter, Coagulase-Positive Staphylococci (CPS), Listeria monocytogenes (Lm), Salmonella and Shiga-toxin-producing Escherichia coli (STEC), in agreement with their respective NRL networks, identified the need to draft a common guidance document, defining:
•    criteria for NRLs to organize PTs in their respective scope;
•    if PTs are outsourced:
-    criteria to outsource (parts of) PTs organised by NRLs for national networks, including PT steps that can be outsourced or not;
-    criteria to select PT providers.
This document [link] gives only guidance, since organisation of PTs at national level is a Member State’s responsibility. The document is based upon an  EURL European Union Reference Laboratory (European Union Reference Laboratory)(European Union Reference Laboratory )-Listeria monocytogenes document on the same topic.