Clinical perspective, offered as context rather than as advice. 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.

wendy_avl said:

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

Coming at wendy_avl’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.

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.

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

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.