Adding the clinical framing, because it changes how the question reads. The version of this that has an answer is narrower than the version being asked. Narrow it and it becomes tractable; leave it broad and the thread will produce nine confident and incompatible replies.
Ask again with the specifics and you will get a better answer than this one.
SarahChen_PharmD said:The version of this that has an answer is narrower than the version being asked.
This matches mine closely enough to be worth saying so out loud. I had assumed I was the exception until I read this.
SarahChen_PharmD said:The version of this that has an answer is narrower than the version being asked.
Coming at SarahChen_PharmD’s question from a different direction. Order of operations matters more than any single choice here: establish a baseline, change one thing, wait long enough for it to express itself, then measure again under the same conditions.
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Shop Reference StandardsAdding the numbers, since they settle part of this. If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way. Most of the apparent contradictions in these threads dissolve at that step.
Moderator note: the sourcing question belongs in the vendor section and has been split out. Report rather than reply if it drifts again.