Evaluating Evidence in Medicine

EBM+ is a consortium whose members are keen to develop the methods of evidence-based medicine to handle evidence of mechanisms in addition to evidence of associations.

What is EBM?

Causal claims are crucial in medicine. Bugs, injuries and environmental factors cause disease and other symptoms; medicines, other treatments and public health policies alleviate or prevent such problems. Evidence-based medicine is a collection of methods for evaluating the evidence for and against causal claims like these. It provides grading systems and hierarchies of evidence, to help weigh up the evidence and to help decide whether there is sufficient evidence to establish a causal claim.

What is EBM good at?

EBM is good at weighing statistical evidence of associations. Statistical trials are used to test whether there is an association between the putative cause and effect. These trials vary in size and methodology, and EBM has developed ways of ranking these statistical studies.

What is EBM bad at?

EBM is bad at a few things, such as detecting reference classes within populations.  For example, blood pressure trials are typically administered on clean populations, whereas the treatment is usually given to people with multiple morbidities. EBM is also affected by 'pragmatic' clinical trials - i.e. hardly any trials are done on pregnant women or for drugs with little financial promise. More generally, EBM does not account for the fallibility of randomised controlled trails (RCTs), most notably in their lack of mechanisms to support correlative evidence.

Read more: http://ebmplus.org


 The EBM+ research project is jointly funded by