A note from our Guild President, Tom Carroll
We have covered the rapidly-evolving topic of psychedelics as medicine in previous posts. One problem with the (one might say, literally) incredible claims about the near-miraculous benefits of psychedelics for a variety of psychiatric conditions is that the psychedelic experience is so unmistakable. This means that the vast (>90%) of those who should be blinded to group assignment in studies, both participants and therapists, are able to correctly guess which group (placebo or active treatment) they were assigned to.*
This means that while study participants can be randomized, they cannot be effectively blinded, arguably making all randomized controlled trials (RCTs) not blinded (i.e., “open-label”). As a consequence, we cannot make a true cause-effect claim about psychedelics based on these trials. Additionally, any positive treatment effects are truly due to psychedelics are likely to be overestimated by these (effectively) open-label studies.
Interestingly, there is a new article our that took a very different approach. This article was just published:
Their results are interesting, including:
- Psychedelic Assisted Therapy (PAT) trials, most of which attempted blinding, showed PAT to be no more effective than antidepressants when tested in in open-label trials.
- Open-label trials of antidepressants showed better (apparent) treatment effects than blinded trials of antidepressants. Interestingly, the same was not true for PAT trials.
Their conclusions:
So, when the claim is made that psychedelics are the cure-all for X condition, we should keep in mind that they are incredibly difficult to study, thus far the data are confounded and, I would argue, we need to be very careful about drawing cause-effect conclusions from non-blinded studies.
More to come, I’m sure, so stay tuned!
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* Bogenschutz, M. P., S. Ross, S. Bhatt, T. Baron, A. A. Forcehimes, E. Laska, S. E. Mennenga, K. O’Donnell, L. T. Owens, S. Podrebarac, J. Rotrosen, J. S. Tonigan and L. Worth (2022). “Percentage of Heavy Drinking Days Following Psilocybin-Assisted Psychotherapy vs Placebo in the Treatment of Adult Patients With Alcohol Use Disorder: A Randomized Clinical Trial.” JAMA Psychiatry 79(10): 953–962.
