Medicine, Health Care and Philosophy

, Volume 16, Issue 3, pp 525–532 | Cite as

Plausibility and evidence: the case of homeopathy

  • Lex Rutten
  • Robert T. Mathie
  • Peter Fisher
  • Maria Goossens
  • Michel van Wassenhoven
Scientific Contribution


Homeopathy is controversial and hotly debated. The conclusions of systematic reviews of randomised controlled trials of homeopathy vary from ‘comparable to conventional medicine’ to ‘no evidence of effects beyond placebo’. It is claimed that homeopathy conflicts with scientific laws and that homoeopaths reject the naturalistic outlook, but no evidence has been cited. We are homeopathic physicians and researchers who do not reject the scientific outlook; we believe that examination of the prior beliefs underlying this enduring stand-off can advance the debate. We show that interpretations of the same set of evidence—for homeopathy and for conventional medicine—can diverge. Prior disbelief in homeopathy is rooted in the perceived implausibility of any conceivable mechanism of action. Using the ‘crossword analogy’, we demonstrate that plausibility bias impedes assessment of the clinical evidence. Sweeping statements about the scientific impossibility of homeopathy are themselves unscientific: scientific statements must be precise and testable. There is growing evidence that homeopathic preparations can exert biological effects; due consideration of such research would reduce the influence of prior beliefs on the assessment of systematic review evidence.


Homeopathy Plausibility Bias Pre-trial belief Randomised controlled trial Review 


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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  • Lex Rutten
    • 1
  • Robert T. Mathie
    • 2
  • Peter Fisher
    • 3
  • Maria Goossens
    • 4
    • 5
  • Michel van Wassenhoven
    • 6
  1. 1.BredaThe Netherlands
  2. 2.British Homeopathic AssociationLutonUK
  3. 3.Royal London Hospital for Integrated MedicineLondonUK
  4. 4.Department of General PracticeKatholieke Universiteit LeuvenLeuvenBelgium
  5. 5.Unit of Genetic Epidemiology, Department of Public Health and EpidemiologyUniversity of BirminghamBirminghamUK
  6. 6.Belgian Homeopathic Medicines Registration Commission (AFMPS)BrusselsBelgium

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