andrew_nyc said:

The distinction that resolves most of these threads is between what is true on average and what is true for one person.

Coming at andrew_nyc’s question from a different direction. 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.

One concrete data point for the thread. 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.

A narrower follow-up, since the general answer is now clear:

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

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…

I read this differently. The confidence in this thread is running ahead of the evidence, and I would rather the uncertainty were stated than smoothed over because it is unsatisfying.

Closing the loop on my own question.

Reporting back for the archive rather than for the thread: I did the narrow version of what was suggested, gave it the full interval, and it settled. Posting it because threads without a follow-up are half a thread.