OMB Meeting Book_9-11-14

9/10/2014 Copyright 2006,2012 by AOAC International, all rights reserved.

AOAC International Interlaboratory Study Workbook

Version:

2.1

Blind (Unpaired) Replicates

AOAC 2011.10 Determination of Vitamin B12

Study name: Study date:

7/24/2014

Study Reported Values

Seq.

Item

Symbol

CLC10-B

E29VLV

Sample ID:

10 a

10 b

Total number of laboratories Total number of replicates

p

1 2 3 4 5 6 7 8

Sum(n(L)) XBARBAR

20

20

Overall mean of all data (grand mean) f Repeatability standard deviation Reproducibility standard deviation Repeatability relative standard deviation Reproducibility relative standard deviation

43.6551 3.0112 3.8583

0.4280 0.0208 0.0305

s(r) s(R)

RSD(r) RSD(R)

6.90 8.84

4.85 7.13

HORRAT value

0.34

0.20

a One laboratory excluded - Failed Single and Double Grubbs Test b One laboratory excluded - Failed Single Grubbs Test c One laboratory excluded - Failed Double Grubbs Test d Includes single determinations for 4 laboratories because of mislabeled product cans. e One laboratory excluded - Failed Cochran Test f Overall mean in mcg/100g RTF for all samples except CLC10-B. CLC10-B overall mean in mcg/kg powder