The statistical evaluation of the interlaboratory comparison is defined in ISO 13528 and ISO 5725-2.

157 testing laboratories from 35 countries all over the world participated in 68 individual test methods in the last proficiency test OFI-pts2019.

Argentina Japan
Australia Jordan
Austria Korea
Bangladesh Lativia
Belgium Malaysia
Bulgaria Norway
China Poland
Colombia Romania
Croatia Slovakia
Czech Republic Slovenia
Finland South Korea
France Spain
Great Britain Sweden
Greece Switzerland
Hungary The Netherlands
Iran Turkey
Israel USA
Italy  


Evaluation parameter

Outlier according to Grubbs’ test
Outlier according to Cochran’s test
z-score
Youden-Plot (Scatter diagram)