Hair loss timeline — need advice

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

How would you tell the difference between that and the alternative explanation?

hank_denver said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

Worth saying that the confident version of this is more useful to the person writing it than to the person reading it.

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.

hank_denver said:

For anyone reading later: the numbers in this thread are worth checking against a primary source before you act on them, including mine.

This is exactly what I could not find anywhere else.

Adding the clinical framing, because it changes how the question reads. 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.

I would rather be corrected than agreed with, if it comes to it.