AOAC Gluten Quantitative Validation Guidance-Round 1(Nov 2023)

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fit1<- fitVCA(form=Result~(Lot+Analyst)/TP, Data=Data2) # Analyst not nested within Lot

fit2<- fitVCA(form=Result~Lot/Analyst/TP, Data=Data2) # Analyst nested within Lot 122 Note in this package in R (as with most ANOVA procedures in R) you should not include the lowest order 123 factor in the model statement. If you do, the ANOVA table will be incorrect. It is assumed that the 124 lowest factor will be nested. The lowest order factor will be listed in the ANOVA Table as "error.”

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Example Code with Datasets Data set A1a for Design 1a:

Lot

Analyst

TP

Well

Result

1 1 1 1 1 1 2 2 2 2 2 2

1 1 1 2 2 2 1 1 1 2 2 2

1 2 3 1 2 3 1 2 3 1 2 3

1 1 1 1 1 1 1 1 1 1 1 1

120.6905 108.5775 118.6613 101.8921 106.5847 110.5391 100.3254 109.5876 108.2381 99.84244 95.70943 97.8807

129 Here, Analyst is a stand-in variable name for Analyst/Day/Calibration, TP is the name for Test 130 Portion/extraction. Since there was only 1 well per test portion, the variable “Well” is not really a factor 131 in the experiment. 132 R-Code for Data Set A1a 133 library(VCA) 134 DataA1a<- read.csv("Test Data A1a.csv") 135 fit1<- fitVCA(form=Result~(Lot+Analyst), Data=DataA1a) # Analyst not nested within Lot 136 fit1 137 fit2<- fitVCA(form=Result~Lot/Analyst, Data=DataA1a) # Analyst nested within Lot 138 fit2.nested 139 varPlot(form=Result~Lot/Analyst/TP, Data=DataA1a, 140 YLabel = list(text="Result", las=0, line=3, cex=1.5), 141 Title= list(main="GFA TEST DATA RESULTS PLOT SET A1a", cex.main= 1.75), 142 Points= list(pch=20, cex=2.50, col="blue"), 143 #MeanLine=list(var="int"), 144 MeanLine=list(var=c("Day", "int"), col="blue")

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Data Output

147

Analyst not nested within Lot

Result ~ (Lot+Analyst)