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In this piece, we discuss the role of blinding and expectancy in psychedelic trials, and place this in a broader historical and contemporary context of blinding in trials across the rest of healthcare. We suggest that premature and uncritical promotion (\u2018hype\u2019) of psychedelics as medicines is not only misleading, but also directly influences participant expectancy in ongoing psychedelic trials. We argue that although psychedelic trials are likely to significantly overestimate treatment effects by design due to unblinding and expectancy effects, this is not a unique situation. Placebo-controlled RCTs are not a perfect fit for all therapeutics, and problems in blinding should not automatically disqualify medications from licencing decisions. We suggest that simple practical measures may be (and indeed already are) taken in psychedelic trials to partially mitigate the effects of expectancy and unblinding, such as independent raters and active placebos. We briefly suggest other alternative trial methodologies which could be used to bolster RCT results, such as naturalistic studies. We conclude that the results of contemporary placebo-controlled RCTs of psychedelics should neither be dismissed due to imperfections in design, nor should early data be taken as firm evidence of effectiveness.<\/jats:p>","DOI":"10.1007\/s00213-022-06221-6","type":"journal-article","created":{"date-parts":[[2022,9,5]],"date-time":"2022-09-05T08:10:45Z","timestamp":1662365445000},"page":"3047-3055","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":99,"title":["Expectancy in placebo-controlled trials of psychedelics: if so, so what?"],"prefix":"10.1007","volume":"239","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9734-6539","authenticated-orcid":false,"given":"Matt","family":"Butler","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luke","family":"Jelen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James","family":"Rucker","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2022,9,5]]},"reference":[{"key":"6221_CR1","doi-asserted-by":"publisher","first-page":"1989","DOI":"10.1007\/s00213-022-06123-7","volume":"239","author":"Jacob Aday","year":"2022","unstructured":"Aday Jacob, Heifets Boris D, Pratscher Steven D, Bradley Ellen, Rosen Raymond, Woolley Joshua (2022) Great expectations: recommendations for improving the methodological rigor of psychedelic clinical trials. 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