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

range, e.g., at the middle of the calibration curve and upper end of the calibration curve.” The gluten document just refers to Table 3 – do we need to add the paragraph above to the gluten doc for clarity? Added a similar paragraph, which reads “At least 4 concentrations per matrix/gluten source combination, including a zero/blank, must be included in the study. The “Low” concentration should be less than or equal to two times the stated LOQ of the method, provided this is less than or equal to 20 mg/kg (if not, then the “Low” concentration should be 20 mg/kg). Other concentrations should span the calibration range, e.g., at the middle and upper end of the calibration curve.” In the description of the intermediate precision, a sentence was added that says “At least 4 concentrations per matrix/gluten source combination, including a zero/blank, must be included in these studies as well.“ Page 8, Right Column, Repeatability Only : Add a target in the absence of an SMPR or ERP (PTM methods) similar to the recovery section. Perhaps 30% RSD [Allergen document added the following sentence at the end of the last paragraph in this section “In the absence of an SMPR and ERP, acceptable RSDr values for food allergen immunoassays are generally ≤20% ”] Added the sentence “In the absence of an SMPR and ERP, acceptable RSD r values for gluten immunoassays are generally ≤20% within the claimed measurement range of the assay. ” Page 10, Product Stability and Consistency : Consider to add the possibility to provide internal stability and lot to lot data, comparable to line 957 (6.2.4.4.5.) “Alternatively, method developers may provide internal lot-to-lot and stability data for review.” [This text was added in the allergen document] Added the sentence “Alternatively, method developers may provide internal lot-to-lot and stability data for review, as long as the volume of data meets or exceeds the data requested in the product stability and consistency studies described here.” Page 11, Section 6.2 : Who will decides (on what criteria) if five labs are sufficient? [This section now reads “Based on AOAC Appendix D guidelines, studies must have a minimum of 8 laboratories submitting valid data (to avoid unduly large confidence bands about the estimated parameters). Only in special cases of very expensive equipment or specialized laboratories may the study be conducted with a minimum of 5 laboratories.”, but in the allergen doc they removed that last sentence about 5 labs] The sentence about special cases where 5 labs can be used was removed. Page 12 section 6.5: What do total and marginal recovery mean? I never heard of them. [This section now has a bullet point that reads “Recovery must be reported, with calculations using the known quantity of target present in incurred test materials based on gravimetric calculations and accounting for any mass balance changes occurring during food processing (e.g., moisture loss during baking). In almost all instances, total recovery is the most appropriate for food allergens as the target allergen should be absent from the blank matrices. Only in rare cases would marginal recovery be applicable.” In the allergen doc, they removed the last two sentences] Also removed those last two sentences discussing total/marginal recovery. Page 12 Section 6.5, LOQ : If estimation of LOD and LOQ is within the scope of the collab study, what is the further usage of these estimates? Are these for informational purposes only, or should these be the official LOD / LOQ values of the method (instead of the SLV LOD / LOQ values)? Additional confusion comes from 5.4.6.3.1.3. and 5.4.6.3.1.4., where probably “SLV” needs to be replaced by “collab study”.