, Volume 33, Issue 2, pp 339–360

Mechanisms and the Evidence Hierarchy


  • Brendan Clarke
    • Science and Technology StudiesUniversity College London
  • Donald Gillies
    • Science and Technology StudiesUniversity College London
    • Science and Technology StudiesUniversity College London
  • Federica Russo
    • Dipartimento di Studi UmanisticiUniversità degli Studi di Ferrara
  • Jon Williamson
    • Philosophy, SECLUniversity of Kent

DOI: 10.1007/s11245-013-9220-9

Cite this article as:
Clarke, B., Gillies, D., Illari, P. et al. Topoi (2014) 33: 339. doi:10.1007/s11245-013-9220-9


Evidence-based medicine (EBM) makes use of explicit procedures for grading evidence for causal claims. Normally, these procedures categorise evidence of correlation produced by statistical trials as better evidence for a causal claim than evidence of mechanisms produced by other methods. We argue, in contrast, that evidence of mechanisms needs to be viewed as complementary to, rather than inferior to, evidence of correlation. In this paper we first set out the case for treating evidence of mechanisms alongside evidence of correlation in explicit protocols for evaluating evidence. Next we provide case studies which exemplify the ways in which evidence of mechanisms complements evidence of correlation in practice. Finally, we put forward some general considerations as to how the two sorts of evidence can be more closely integrated by EBM.


MechanismDifference-makingEvidenceEvidence of mechanismEvidence in medicineEvidence-based medicine

Copyright information

© Springer Science+Business Media Dordrecht 2013