The psychedelic Dodo Bird: Why our usual research methods miss the mark

Abstract Psychedelic-assisted therapy (PAT) may be approaching its own “Dodo Bird” moment: the appearance that multiple psychotherapeutic modalities “work” equally well, not because they are interchangeable, but because both symptom-focused outcome measures and, more fundamentally, the assumptions embedded in dominant RCT paradigms are ill-suited for probing the dynamic, relational, and meaning-making processes that drive therapeutic change in PAT. We argue that case-based, process-oriented, and observational approaches are better suited to capturing these dynamic processes, and that to discern differences across modalities it is necessary to use measures attuned to normative foundations of each respective framework. However, even when such processes are more adequately examined, PAT is unlikely to converge on a single optimal modality; rather, different therapeutic modalities are likely to be optimally effective for different individuals within specific contexts. Recognizing this pluralism reframes the central scientific task—not as identifying one superior intervention, but as understanding for whom, under what conditions, and through which relational and meaning-making processes diverse PAT modalities facilitate transformation. As psychedelic-assisted therapy (PAT) research continues to prioritize treatment standardization and mechanistic isolation—assumptions suited to pharmacological interventions but misaligned with therapies that derive their effects through context, relationship, and subjective meaning—the field risks repeating epistemological errors that decades of psychotherapy research have already revealed. To avoid this fate, we must revisit what counts as evidence and how it is generated.