Table 4. Method accuracy assessed in the analyses of ergot alkaloids in rye certified reference material (CRM).

Alkaloid	Measured				Certified			|wCRM–w| µg/kg	Uc = µg/kg	|wCRM–w|< Uc
	w µg/kg	N	U ±µg/kg		wCRM µg/kg	N	UCRM ±µg/kg
Em	262	7	29		595	5	745	332	537	+
Es	540	6	43		537	5	260	3	193	+
Et	1396	10	112		1349	5	1156	47	840	+
Eco	728	10	57		614	5	156	114	446	+
Ekr	597	8	65		570	5	52	27	76	+
Ecr	1091	8	99		923	5	195	168	172	+
Emn	116	7	12		335	5	758	219	546	+
Esn	242	8	27		331	5	476	89	952	+
Etn	333	10	42		464	5	367	161	267	+
Econ	334	10	35		362	5	391	28	284	+
Ekrn	380	7	44		477	5	526	131	381	+
Ecrn	371	8	39		462	5	469	91	340	+

w=measured mass fraction and w_CRM=CRM mass fraction of ergot alkaloids
U_CRM=uncertainty of CRM value expressed as 95% of confidence interval for U_CRM= in Student’s t-distribution,
U_c=extended combination of CRM value uncertainty (U_CRM) and measured value uncertainty (U) at extension coefficient k=2. Abbreviations as in Table 1