Mechanisms and the evidence hierarchy
Lead Research Organisation:
University of Kent
Department Name: Sch of European Culture and Languages
Abstract
Evidence-based medicine is a relatively recent technique for supporting clinical decisions by the 'conscientious, explicit, and judicious use of current best evidence' (Sackett et al. 1996. BMJ. 312: 71). This 'best evidence' usually has a very specific meaning: the best evidence available to support decision-making in medicine is that arising from clinical trials, where treatments are tested on large numbers of patients. On the other hand, evidence of mechanisms - usually characterized as knowledge gained from experimental investigations in the laboratory - is held to be of low quality by the EBM practitioner.
However, recent work in the philosophy of causality has suggested that this hierarchical interpretation of evidence is problematic.
Decisions about treatment make a difference to the health of individuals. Therefore it is of utmost importance to develop a concept of evidence that maximizes the available sources of evidence (trials, results of lab experiments) and minimizes the risks of errors in various medical decisions.
In this project, we aim to investigate the relationship between evidence-based medicine, evidence of mechanisms, and causality from a number of different theoretical and practical perspectives including philosophy of causality, philosophy and history of medicine, and medical practice.
Via collaborative workshops, and participation in an international conference in September 2012, both involving philosophers, historians and a number of medical scientists and practitioners, the members of the investigating team will probe these issues deeply.
However, recent work in the philosophy of causality has suggested that this hierarchical interpretation of evidence is problematic.
Decisions about treatment make a difference to the health of individuals. Therefore it is of utmost importance to develop a concept of evidence that maximizes the available sources of evidence (trials, results of lab experiments) and minimizes the risks of errors in various medical decisions.
In this project, we aim to investigate the relationship between evidence-based medicine, evidence of mechanisms, and causality from a number of different theoretical and practical perspectives including philosophy of causality, philosophy and history of medicine, and medical practice.
Via collaborative workshops, and participation in an international conference in September 2012, both involving philosophers, historians and a number of medical scientists and practitioners, the members of the investigating team will probe these issues deeply.
Planned Impact
It is hoped that this exploratory project on mechanisms and the evidence hierarchy will lead to work that impacts both on the relevant academic fields - philosophy of causality and medicine, history of medicine, medical practice - and on medical practice and the public understanding of medicine.
How we will maximise impact in relevant academic fields:
- Most importantly, we will have representatives from the above fields engaged in the project team, so that a team member is well placed to advise on dissemination in each field. Regular interdisciplinary meetings will ensure that the whole team is engaged with all the issues, so that the ideas generated are responsive to all the relevant fields, and so are of interest to and accessible to all these fields.
- Further, we have plans to maximize dissemination across fields:
* Our first publication will be a highly accessible position paper in a leading medical journal.
* Our second publication will be a more detailed paper in a leading philosophy of science journal.
* Our two workshops will allow dissemination to interested scientists, while we also get their input into the development of our ideas.
* A session at our final conference will allow a wider audience to hear our work, and also offer further feedback.
* Team members will take part in various interdisciplinary seminars and reading groups, as detailed in our 'Case for support'.
How we will maximise impact in medical practice:
- Previous philosophical projects in similar areas have had substantial impact on medical practice, with recent contributions from philosophers of science appearing in leading medical journals.
- We have chosen to engage a number of prominent medical scientists in this project because we value their input, but this will also increase the chances of our project successfully impacting on the lively debate over the methods and practices of evidence-based medicine already occurring in medicine. So our project will have substantial reach in medical practice.
How this research can eventually impact on the public:
- Understanding what evidence is needed for medical practice is also important for the layman. Doctors can provide better explanations for their diagnosis and decisions if they can appeal to a clear and correct concept of evidence.
- In the planned outreach activities, we will endeavour to make our research accessible:
* An accessible position paper in a medical journal is likely to be read by some journalists interested laymen.
* Members of the public will be very welcome to attend our final conference.
* We will organize a dedicated public event at the Dana Centre gathering together medical practitioners, philosophers and historians of medicine.
* We will also give notice of our events and popular explanations of our work using venues such as Linkedin and Facebook.
How we will maximise impact in relevant academic fields:
- Most importantly, we will have representatives from the above fields engaged in the project team, so that a team member is well placed to advise on dissemination in each field. Regular interdisciplinary meetings will ensure that the whole team is engaged with all the issues, so that the ideas generated are responsive to all the relevant fields, and so are of interest to and accessible to all these fields.
- Further, we have plans to maximize dissemination across fields:
* Our first publication will be a highly accessible position paper in a leading medical journal.
* Our second publication will be a more detailed paper in a leading philosophy of science journal.
* Our two workshops will allow dissemination to interested scientists, while we also get their input into the development of our ideas.
* A session at our final conference will allow a wider audience to hear our work, and also offer further feedback.
* Team members will take part in various interdisciplinary seminars and reading groups, as detailed in our 'Case for support'.
How we will maximise impact in medical practice:
- Previous philosophical projects in similar areas have had substantial impact on medical practice, with recent contributions from philosophers of science appearing in leading medical journals.
- We have chosen to engage a number of prominent medical scientists in this project because we value their input, but this will also increase the chances of our project successfully impacting on the lively debate over the methods and practices of evidence-based medicine already occurring in medicine. So our project will have substantial reach in medical practice.
How this research can eventually impact on the public:
- Understanding what evidence is needed for medical practice is also important for the layman. Doctors can provide better explanations for their diagnosis and decisions if they can appeal to a clear and correct concept of evidence.
- In the planned outreach activities, we will endeavour to make our research accessible:
* An accessible position paper in a medical journal is likely to be read by some journalists interested laymen.
* Members of the public will be very welcome to attend our final conference.
* We will organize a dedicated public event at the Dana Centre gathering together medical practitioners, philosophers and historians of medicine.
* We will also give notice of our events and popular explanations of our work using venues such as Linkedin and Facebook.
Organisations
People |
ORCID iD |
| Jon Williamson (Principal Investigator) | |
| F Russo (Co-Investigator) |
Publications
Clarke B
(2013)
The evidence that evidence-based medicine omits.
in Preventive medicine
Clarke B
(2013)
Mechanisms and the Evidence Hierarchy
in Topoi
Clarke B
(2013)
Modelling mechanisms with causal cycles
in Synthese
Gillies D
(2013)
Should causal models always be Markovian? The case of multi-causal forks in medicine
in European Journal for Philosophy of Science
Kelly MP
(2014)
The integration of social, behavioral, and biological mechanisms in models of pathogenesis.
in Perspectives in biology and medicine
Russo F
(2012)
EnviroGenomarkers: The Interplay Between Mechanisms and Difference Making in Establishing Causal Claims
in Medicine Studies
Williamson J
(2013)
How Can Causal Explanations Explain?
in Erkenntnis
| Description | Since the advent of Evidence-Based Medicine (EBM), hierarchies of evidence have been widely used to guide the evaluation of evidence for causal claims. These hierarchies focus on statistical evidence for causal claims, and tend to champion the use of randomised controlled trials (RCTs). This project explored the question of whether evidence of mechanisms should have a place in evidence hierarchies, complementing statistical evidence such as that obtained from RCTs. The project concluded that mechanistic evidence should indeed play a more prominent role in explicit hierarchies of evidence, for two reasons. First, recent work in the philosophy of causality and the history of medicine suggests that in order to establish a causal claim one needs to establish both a statistical connection between the putative cause and the putative effect and a mechanistic connection that can explain the statistical connection. Second, discussion with medical scientists and public health policy makers revealed that such practitioners often do take mechanistic evidence into account, but mostly in a tacit or implicit way, in contravention to the explicit recommendations of the hierarchies of evidence. |
| Exploitation Route | Evidence hierarchies are widely applied in medicine and public health policy as well as the social sciences. If the conclusions of the project are correct, they should be of interest to all these areas. |
| Sectors | Healthcare |
| URL | https://blogs.kent.ac.uk/jonw/projects/mechanisms-and-the-evidence-hierarchy/ |
| Description | Our findings have helped to inform debate about how to improve evidence-based medicine. This impact has involved public health practitioners who are charged with drawing up guidelines and protocols for causal discovery in medicine. Such debate took place at the conference ECitS 2012 (Evidence and Causality in the Sciences, University of Kent, UK, 5-7 September 2012), at a public engagement event (The hierarchy of evidence, Archaeology Lecture Theatre, Archaeology building, UCL, 5.30-7.30pm Monday 10th September 2012), and at three project workshops. The project led to the creation of the EBM+ consortium, whose members are interested in improving the way in which evidence based medicine handle mechanistic evidence. The EBM+ consortium (www.ebmplus.org) continues the debate initiated by this project. |
| First Year Of Impact | 2012 |
| Sector | Healthcare |
| Impact Types | Societal |