Is buying from overseas even worth the hassle — my results so far

Dr.AddMedPHL said:

My experience ordering cross-border ordering internationally: I've ordered from a UK pharmacy.

I read this differently from Dr.AddMedPHL, on substance rather than tone. Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions. What is a personal-import allowance in one country is a controlled-import offence in another.

That is the short version; the long version is somebody else's post.

The figures, for anyone assembling their own picture. Give anything pharmacological four weeks before you judge it, and give anything measured weekly a four-point rolling average before you call it a trend.

Dr.BariatricHTX said:

Import rules are jurisdiction-specific and this board keeps giving US-shaped answers to non-US questions.

Coming at Dr.BariatricHTX’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.

One thing that is still open after NurseAsh_DET’s answer:

What would you measure differently if you were starting again?

OP back with an update, since a thread like this is useless without one.

Closing the loop. The answer turned out to depend on the detail I had left out of the opening post, which is a lesson about how to ask rather than about the subject.