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Combined Interpretations of the 2003, 2009, and 2016 Standards that apply to Volume 1 of the 2016 TNI Standard


MODULE 5: MICROBIOLOGY TECHNICAL REQUIREMENTS
Section: 1.6.4.2

Question:  For ongoing DOC e.g. for HPC SimPlate, the lab performs a blind PT sample or a Quality Control sample with results meeting the manufacturer's acceptance criteria. However, we would like to be able to use section 1.6.3.2.e) "A documented process of reviewing QC samples performed by an analyst, or groups of analysts, relative to the QC requirements of the method, laboratory SOP, client specifications, and/or this Standard. This review can be used to identify patterns for individuals or groups of analysts and determine if corrective action or retraining is necessary."

SM/TNI requires repeat counts performed monthly with criteria of 5% RPD for a single analyst or 10% for more than one analyst counting. Can this process be applicable or acceptable to meet section 1.6.3.2.e and be applied for continuing DOC for other analyst who did not actually perform the PT or QCS? If not, please expand on exactly what this section mean with a clear example.

TNI Response:  Your example would apply to 1.6.3.2.e if the analyst using 1.7.3.3 only read out positive results for that method. Please note that 1.7.3.3 does not include determination of non-positive environmental or QC samples, and therefore a DOC following 1.6.3.2.e using 1.7.3.3 would not prove an analyst competent in determining non-positive environmental or QC sample results or competent at performing any other parts of the method. Therefore 1.7.3.3 cannot be used solely to meet the requirements for an ongoing DOC.

1.6.3.2.e refers to those instances where a lab may use other approaches to an on-going DOC, such as lab generated blind samples, replicate analysis, in-batch positives and negatives or other reasonable approaches. If the laboratory has a documented procedure for analyzing samples using the method, utilizing associated techniques (ex. aseptic technique) and meeting QC requirements, on a defined basis in a similar manner for all analysts (such as monthly positive and negative QC samples for each analyst), which could be used to determine patterns/trends, it could be used as documentation for an on-going DOC.