Twoin-housereferencematerials(IHRMs)werepreparedatdifferent
levelsofanalyteconcentrationandthehomogeneityrequiredwasverifiedfortheintendeduse.
AsetofparametricandrobuststatisticaltestswereappliedtoevaluatetheassignedvaluesofeachIHRM.
MetrologicalcompatibilityassessmentofPTresults,evaluationofindividualandglobalperformanceofthelaboratories,anddeterminationofuncertaintyoftheanalyticalmeasurementswereevaluatedin
this restrictedstudyscenario