AOAC SPIFAN Nutrients ERP (December 7, 2022)

Amino-07 (SLV) 10-2022 FOR ERP USE ONLY DO NOT DISTRIBUTE

= Γ ( , )

eqn 24 where: = p -value; probability of observing data at least as extreme as test statistic Γ = cumulative Student’s t- distribution function = test-statistic; expression using sample estimates of characteristics of the population = − 2 degrees of freedom = number of replicate pairs of results concentration of analyte in spiked sample = concentration of analyte in sample = concentration of analyte in spike = � − 1.96 × √ , + 1.96 × √ � where: = lower, upper limits of confidence interval = mean of value of data set = standard deviation of data set = number of values in data set eqn 26 = − × 100 eqn 25 where: = recovery =

p -value

Recovery recovery (%)

95% confidence interval

= ∑ + /2 − ∑ − /2

Robustness estimated effect of factor

eqn 27

where: = the effect of x on response Y Y + , Y − = where: 1 = final estimate of standard error = where: 0 = initial estimation of error | | = median effect for all | | ≤ 2.5 × 0 0 = 1.5 × | |

the sums of the (corrected) responses where x is at the extreme levels + and − = number of experiments of the design the number of absolute effects < 2.5 × 0 = the value of effect

final estimation of standard error 1 = � −1 ∑ 2

eqn 28

initial estimation of error

eqn 29