Comment on Open thread, Dec. 14 - Dec. 20, 2015

Wed, 16 Dec 2015 18:34:49 GMT

I think this part is a bit too strong, which corrupts one of the main points of the whole post:

The other contribution comes from the get-better-anyway effect. This is a statistical artefact and it provides no benefit whatsoever to patients.

It's not called the stay-the-same-anyway effect, it's called the get-better-anyway effect. The patient who reports lower pain a week later actually is in less pain. Health isn't repeated draws from an urn: if you crack a rock one day it won't regress to the mean. It'll stay cracked. That people heal is not a statistical artefact.

That is, I agree much more with the O'Connell quote (emphasis mine):

If this finding is supported by future studies it might suggest that we can’t even claim victory through the non-specific effects of our interventions such as care, attention and placebo. People enrolled in trials for back pain may improve whatever you do. This is probably explained by the fact that patients enrol in a trial when their pain is at its worst which raises the murky spectre of regression to the mean and the beautiful phenomenon of natural recovery.

Regression to the mean plays a part, especially for chronic variable conditions like lower back pain or depression, but even there natural recovery plays a huge part (otherwise the condition would be a degenerative one).

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