I have written extensively on hierarchies of evidence in evidence-based medicine. The origin story of hierarchies of evidence is a little contentious. Several sources in EBM cite Campbell and Stanley’s 1963 classic “Experimental and Quasi-experimental Designs for Research” as containing the first hierarchy, or at least the germ of the …
Do you have an idea of what makes good medical evidence in your mind? Do you have ideas about the kind of evidence you’d pay attention to, and the kind of evidence you can safely disregard? Or ideas about the evidence that would strongly sway your beliefs and actions, and …
In the early part of the 20th century, the philosopher Ludwig Wittgenstein sought to demonstrate that metaphysical claims are meaningless. Statements which couldn’t be proven true in some way—through logic or evidence—weren’t even false, they had no meaning at all. But he ran up against a problematic irony. His book, …
By definition, I begin, Alternative Medicine, I continue, Has either not been proved to work, or been proved not to work. Do you know what they call alternative medicine that’s been proved to work? Medicine. —Tim Minchin, Storm In his beat-poem Storm, the musician and comedian Tim Minchin lays …
Hierarchies of Evidence are a tool employed by many advocates of Evidence-Based Medicine. They are used to appraise evidence from a range of sources, as well as to teach medical students about evidence and evidence appraisal. My PhD thesis concerns the variation in hierarchies defended, and the range of philosophical …
Randall Monroe of xkcd started writing explanations of complex physical phenomena using only the most common 1,000 English words (or the most common ‘ten hundred’, as he’d have to put it). He recently released a straightforward application which allows writers to check which words fall into his list of 1,000. I’ve …
Hierarchies of evidence can be classified as exhaustive or inexhaustive. A hierarchy is exhaustive if and only if it gives some ranking to any given piece of medical evidence – there’s nothing it leaves out. But there’s a dilemma which hierarchy authors face: either way, hierarchies of evidence present a …
Hierarchies of evidence in Evidence-Based Medicine (EBM) come in many varieties and have been very influential in medical practice and policy since the late 1990s. However, two fundamental problematic assumptions underpin the use of hierarchies of any kind in clinical practice: (1) that evidence can and should be appraised in …
Evidence-Based Medicine is an attempt to simplify and streamline a complex reality into a more manageable structure. Reflective EBM proponents know that matters are very complicated. But they understand that practitioners have very limited time (and abilities) to deal with these complexities. They must use heuristics and simplifications. Sometimes this …
Strength of Recommendation hierarchies such as SORT and GRADE go a step further than your standard hierarchy of evidence. Standard hierarchies tend to rank or rate the evidence provided by a study on a scale of quality, strength or validity. Strength of Recommendation hierarchies are usually two-step processes. First, they …
