Division 9 Method performance characteristics (precision)F1

Statistical results of the interlaboratory test:

• the following table gives the values for egg yolk.

• The following data were obtained from an international method performance study carried out to internationally agreed procedures.

• Year of interlaboratory test:	1998
  Number of laboratories:	24
  Number of samples:	5
  Analyte:	Egg yolk

  Samples	A	B	C	D	E
  Number of laboratories retained after eliminating outliers	19	20	22	20	22
  Number of outliers (laboratories)	3	4	2	4	2
  Number of accepted results	38	40	44	40	44
  Mean value	147,3	241,1	227,4	51,9 (*) 72,8 (*)	191,1
  Repeatability standard deviation (S r ) g/l	2,44	4,24	3,93	1,83	3,25
  Repeatability relative standard deviation (RSD r ) (%)	1,7	1,8	1,8	2,9	1,7
  Repeatability limit (r) g/l	6,8	11,9	11,0	5,1	9,1
  Reproducibility standard deviation (S R ) g/l	5,01	6,06	6,66	3,42	6,87
  Reproducibility relative standard deviation (RSD R ) (%)	3,4	2,5	2,9	5,5	3,6
  Reproducibility limit (R) g/l	14,0	17,0	18,7	9,6	19,2

  Sample types

  A

• Advocaat, blind duplicates

B

• Advocaat, blind duplicates

C

• Advocaat, blind duplicates

D

• Advocaat (diluted), split levels (*)

E

• Advocaat, blind duplicates