Adding the clinical framing, because it changes how the question reads. Most of what circulates confidently in this community traces back to one summary of one study, and the qualifier was dropped somewhere in the third retelling.

HPLC_Greg said:

Give anything pharmacological four weeks before you judge it, and give anything measured weekly a four-point rolling average before you call it a…

There is a second half to this that has not been said yet. The useful move here is to separate what is established from what is widely repeated. Those two sets overlap less than the confident tone of most write-ups suggests, and the second set is where nearly all the disagreement on this board comes from.

Adding the numbers, since they settle part of this. For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine. Half the figures circulating in this community trace back to a secondary summary that dropped a qualifier.

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

How long did you give it before you decided it was working?

Moderator note: the sourcing question belongs in the vendor section and has been split out. Tagging this one for the weekly digest.