AOAC Guidance on FA Immunoassay Validation (August 2023)

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for any mass balance changes occurring during food processing (e.g., moisture loss

during baking).

5.4.5.2.3. Precision estimates reported must include both repeatability (S r and RSD r ) and

reproducibility (S R and RSD R ).

5.4.5.2.4. LOD/LOQ

5.4.5.2.4.1. LOD and LOQ will be estimated using reproducibility (S R and RSD R ). 5.4.5.2.4.2. Data collected from analysis of incurred test materials for all matrices will be used to model the relationship between analyte concentration and reproducibility. Data used must meet other method performance criteria (e.g., 5.4.5.2.4.2.1. LOD will be estimated using a hypothesis test approach, with α = β = 0.05. The relationship between observed concentration and intermediate precision standard deviation must be taken into account in the estimation of LOD (also referred to as a precision profile estimation method for LOD). Full instructions for the calculations to estimate LOD are in Annex C. 5.4.5.2.4.2.2. LOQ estimation will be based on the relationship between concentration and intermediate precision standard deviation. Full instructions for the recovery of 50-150%).

calculations to estimate LOQ are in Annex C.

5.4.6. Acceptance Criteria

5.4.6.1. If an applicable SMPR is available for a method, the collaborative study data must meet the

corresponding criteria.

5.4.6.2. In the absence of an applicable SMPR, an expert review panel will evaluate the study data according to their expert opinions. With respect to recovery, while ideal values are from 80-

120%, values of 50-150% are acceptable. (9)

5.4.6.2.1. LOQ

5.4.6.2.1.1. The LOQ must be greater than or equal to the LOD.

5.4.6.2.1.2. The RSD R at the LOQ must be less than or equal to the RSD R in the relevant SMPR. If there is no SMPR available for a particular food allergen, RSD R at the

LOQ must be ≤ 30%.

5.4.6.2.1.3. If a method developer has an LOQ claimed as part of the method design (e.g., the lowest non-zero calibrant), the estimated LOQ from the collaborative study (which meets the SMPR requirements for maximum RSD R ) must be less than or equal to the claimed LOQ of the kit, within statistical tolerances. If the estimated LOQ from the collaborative study is greater than the claimed LOQ of the kit, the method developer must revise the LOQ claimed in the test kit insert and validation reports to meet the precision requirements for LOQ. 5.4.6.2.1.4. In the validation reports and test kit inserts, the method developers must indicate the actual RSD R value estimated for the LOQ of the kit as part of the

LOQ information. For example:

5.4.6.2.1.4.1. LOQ 15 , for a method where the existing LOQ claimed by the kit had an

estimated RSD R of 15% in the collaborative study