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A possible origin story of OOT-limits - part 3

Updated: Jun 18

In the first part, after the introduction we discussed mostly where we should look around searching for OOT-limits. In the secound part, we did our calculation, and generated good OOT-limit candidates. In this part, we let these outside to play with the others, and observe what happens with them.

How to confirm OOT-limit

One important lesson I learnt when I worked for QC: you may know everything about your control strategy for your product and your analytical methods' lifecycle, but even that is not always enough to fully confirm the OOT-limit. So when you are done with your calculation, always consult with the product owner and QA, because either they are interested in some quality attributes more than you would think, or there may be some quality attributes that are in your QC scope, but e.g., QA knows that a certain attributes is only there due to some misunderstanding with a regulatory authority and it has no quality impact on the product at all. What I would suggest is to make both Production and QA countersign your OOT-limit list.

Lifecycle of OOT-limits

When you confirmed your OOT-limits to use, be sure you handle them in a flexible manner. However scientifically sound document you compiled, you will need to check again with a pair of critical eyes at each OOT-investigation you conduct. And if you run into a false alarm, it's for your own sake to update the limit as fast as you can.

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