This has always been the problem with psychedelics as a therapeutic approach. It's hard to reconcile being a responsible clinician and recommending a therapy with such mixed and often-negative results. They are in charge of a person's mental well-being in a way that people evangelizing psychedelic therapy don't seem to properly appreciate. If a patient is interested in that therapy, they might be a better candidate, but even then... if the results aren't great it's hard to justify.
Don't get me wrong, I have no problem with psychedelics for personal use, and I've seen them do wonderful things for people. But I've also seen them do horrific things to people and I feel like a lot of young people have a great trip and then immediately conclude that literally every human being NEEDS to go out and trip without any more consideration. That same sort of evangelism carries over to the microdosing realm. It may have a place! But personally, I've tried it with psiolocybin, and I found that typical microdoses have a very detrimental effect on my ability to focus.
In the former case, a positive outcome is expected and therefore negative outcomes are in a sense less tolerable, especially since a false positive would lead to people repeatedly microdosing over an extended period of time, to their long-term detriment.
In the latter case, a "negative experience" does not preclude getting the desired results. And an acute negative experience in a one-time dose may be tolerable when contrasted with the long-term severity of the pathology it is meant to treat.
These are not microdosing experiments though. The usual way it is handled is that you get a few weeks of CBT then you get half a dose and the following week you get a full dose followed by more weeks of CBT. There is no placebo effect here that's possible because, well, it is impossible for someone to believe they have taken a full dose of pscychodelic drugs and not feel anything. But you still have a control in this case because you have a group that goes through CBT and another group that goes through CBT + drugs.
In fact, from these studies there have been very little "bad trips", mostly I guess because you have the half-dose session and then the full dose session in a very controlled environment and so on. These experiments are obviously done quite responsibly.
So I think you're mixing things up a little bit and I would suggest doing a little more research in the topic. Psychodelic therapy, at least the kind that is being explored seriously is not really done through microdosing.
From what I recall, a low dose of methylphenidate is used as a control in many studies because it has some of the same side effects without the trip. For psychedelic-naive people who don’t really know what to expect, I could see it being an ok control. Once you’ve experienced a single high-dose trip though… yeah… you’re never going to trick someone with it.
That just means you can't possibly have a proper control. BIG difference.
And there may still be meaningful treatment effects, at least judging by current standard of care for many psychiatric ailments and how those have performed in studies.
Again, I'm quite confident that the effect of many current psychiatric standard of care treatments would never have been picked up by this study. Not because they don't work (at least somewhat), but simply because there is too much noise and natural variability.
Either (1) it has no effect or (2) the strength and direction of the effect are random. Either of those qualities renders the intervention ineffective. You can’t justify giving a patient something that will have no effect, or will make them worse off half of the time when there are more effective options are on the table.
Of course this is comes with the caveat that the study is adequately powered to detect the strength of the effect you are looking for. That being said, there is plenty historical data for the placebo, so I don’t think that being underpowered because of misestimation of the background variance would be an issue.
- Assume that a microdose either improves an outcome, or does nothing. Then, averaged over a large group, such random improvements would lift the group's outcome a little. It's a microdose worth taking.
- Assume that a microdose can both improve and worsen the outcome, or have no effect. If the experimental group's averaged results are indistinguishable from the control group's averaged results, it means that the microdose worsens the outcome about as often and / or as much as it improves it. This, to me. means that a microdose is a gamble not worth taking.
There is, of course, a difference between a microdose having no effect at all, or having an effect which can be either positive or negative. This difference is important for further research. For usage here and now, it's sadly irrelevant.
If a microdose only works when the person taking it knows it works, then it's basically the placebo effect. A good placebo can be useful, at least for commercial purposes.