Biology & Philosophy

, 34:18 | Cite as

Overcoming disagreement: a roadmap for placebo studies

  • Charlotte BleaseEmail author
  • Marco Annoni


In the field of placebo studies residual disagreement about the terminology ‘placebo’ and ‘placebo effect’ still persists. We differentiate between the conceptualization of placebos in clinical trials; and placebo effects understood as a psychobiological phenomenon. With respect to the latter, we argue that a scientific ‘placebo paradigm’ has emerged, indicating that—at least among placebo scientists—there exists relatively stable consensus about how to conceive of placebo effects. We claim that existence of a placebo paradigm does not protect concepts from revision; nonetheless, we argue that scientific progress is dependent on, and guided by relative conceptual stability. Therefore, to mount persuasive arguments for conceptual revision in respect of ‘placebo effects’ we argue, critics either need to defend the claim that a placebo paradigm is not underway, or that there are major scientific failings in respect of it. With these considerations in mind we examine three alternative proposals for conceptual reform: Grünbaum/Howick’s relativity models of placebo concepts; Moerman/Brody’s meaning response; and Nunn/Turner’s proposal for conceptual eliminativism. We derive two conclusions from this evaluation. First, we conclude that no convincing arguments have so far been presented for conceptual overhaul of ‘placebo effects.’ Notwithstanding this analysis, we conclude that refinement of this concept is likely. Second, we agree with Turner and Nunn that the term ‘placebo’ in the context of randomized controlled trials remains a source of confusion for many researchers, risking the design and scientific integrity of clinical findings. Therefore, in these contexts, replacing the term ‘placebo’ with ‘control’ is justified.


Placebo Placebo effect Meaning response Conceptual change Randomized controlled trials Medical epistemology 



The authors thank the two anonymous reviewers and the Editor, Dr. Jay Odenbaugh, for helpful comments on a previous draft of this manuscript.


Charlotte Blease was supported by an Irish Research Council-Marie Skłodowksa Cure Award (CLNE/2017/226) and a Fulbright Award.


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Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Program in Placebo Studies, General Medicine and Primary CareBeth Israel Deaconess Medical Center, Harvard Medical SchoolBostonUSA
  2. 2.School of PsychologyUniversity College DublinDublinIreland
  3. 3.Consiglio Nazionale delle Ricerche (CNR)RomeItaly
  4. 4.Istituto di Tecnologie Biomediche (ITB)RomeItaly

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