@failedLyndonLaRouchite I think observational studies in medicine are valuable, as long as you understand their limitations. This is not interventional, so having a placebo (to refer to your other toot) does not really apply, as they are not testing any procedure or drug.
Follow
@failedLyndonLaRouchite It's a bit like case reports, which are a very important part of the medical literature, they are descriptive by nature (there is no control in these studies either)
@failedLyndonLaRouchite As a biologist, I think of these as the equivalent of an old fashioned descriptive natural history study in botany or zoology. They are a very important part of the literature of the field, so long as you understand their limitations.