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.

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

Dr.AddMedPHL said:

Practical: whatever you change, write down the date and the reason.

Coming at Dr.AddMedPHL’s question from a different direction. There is a difference between no evidence and evidence of no effect, and this subject is one where the two get swapped freely in both directions.

Adding the numbers, since they settle part of this. 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.

Following on from Dr.AddMedPHL — and this may be the naive question:

What did you change at the same time, and can you separate the two now?

Moderator note: good thread. Keeping it here rather than moving it, because the question is general enough to be useful. Thread quality here is what the rules are for. Keep it up.