dan_philly said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

I am going to disagree with the direction of travel here. The thread has converged on the tidiest answer rather than the best-supported one, and those are not the same thing.

Ask again with the specifics and you will get a better answer than this one.

dan_philly said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

True, with the qualification that this is a self-selected group. The people for whom it did not work post less, and that shapes everything we think we know.

dan_philly said:

If you are comparing against somebody else’s result, check that you are comparing the same measurement taken the same way.

Thank you — that is the clearest version of this I have read, and I have read a lot of them.

Clinical perspective, offered as context rather than as advice. If two explanations both fit, the useful question is which one predicts something the other does not. That is answerable; arguing about which sounds more plausible is not.

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

Found this through search years later and it is still the best discussion of the question, so adding one thing. Say what you would expect to see if you were wrong, before you look. It is a small discipline and it changes what you notice.